| Revision history for SPIRV-Tools | 
 |  | 
 | v2022.3-dev 2022-05-31 | 
 |   - General | 
 |     - Add SPV_KHR_fragment_shader_barycentric support (#4805) | 
 |     - Add support for SPV_KHR_subgroup_rotate (#4786) | 
 |   - Optimizer | 
 |     - Fold multiply and subtraction into FMA with negation (#4808) | 
 |     - Add more folding for composite instructions (#4802) | 
 |     - spirv-opt: add pass for interface variable scalar replacement (#4779) | 
 |     - Don't try to unroll loop with step count 0. (#4769) | 
 |   - Validator | 
 |     - spirv-val: Add PerVertexKHR (#4807) | 
 |     - spirv-opt : Add FixFuncCallArgumentsPass (#4775) | 
 |     - spirv-val: Add CullMaskKHR support (#4792) | 
 |   - Linker | 
 |     - linker: Recalculate interface variables (#4784) | 
 |  | 
 | v2022.2 2022-04-07 | 
 |   - General | 
 |     - Add OpModuleProcessed to debug opcode (#4694) | 
 |   - Optimizer | 
 |     - Complete handling of RayQueryKHR type (#4690) | 
 |     - Have scalar replacement use undef instead of null (#4691) | 
 |     - Optimize Instruction::Instruction (#4705) | 
 |     - Handle propagation of arrays with decorations (#4717) | 
 |     - spirv-opt: Add OpExecutionModeId support (#4719) | 
 |     - Optimize Type::HashValue (#4707) | 
 |     - Optimize DefUseManager allocations (#4709) | 
 |     - Add pass to remove DontInline function control (#4747) | 
 |     - Better handling of 0xFFFFFFFF when folding vector shuffle (#4743) | 
 |     - Reset the id bound on the module in compact ids (#4744) | 
 |     - spirv-opt: (WIP) Eliminate Dead Input Component Pass (#4720) | 
 |     - Support SPV_KHR_uniform_group_instructions (#4734) | 
 |     - Handle shaders without execution model in spread-volatile-semantics (#4766) | 
 |   - Validator | 
 |     - Fix handling of Nontemporal image operand (#4692) | 
 |     - [spirv-val] Allow 0 Component Count for DebugTypeArray for Shader (#4706) | 
 |     - spirv-val: Validate DebugTypeMatrix (#4732) | 
 |     - spirv-val: Label Vulkan VUID 04734 (#4739) | 
 |     - spirv-val: Label VUID 06491 (#4745) | 
 |     - spirv-val: Disallow array of push constants (#4742) | 
 |     - spirv-val: Label Vulkan RuntimeArray VUID (#4749) | 
 |     - spirv-val: Add Vulkan Image VUID 06214 (#4750) | 
 |     - spirv-val: Add Vulkan Dref not allowed 3D dim VUID (#4751) | 
 |     - spirv-val: Label and add test for PSB Aligned (#4756) | 
 |     - spirv-val: Add Vulkan 32-bit bit op Base (#4758) | 
 |     - spirv-val: Add more Vulkan VUID labels (#4764) | 
 |   - Diff | 
 |     - Introduce spirv-diff (#4611) | 
 |     - Stabilize the output of spirv-diff (#4698) | 
 |     - spirv-diff: Handle OpSpecConstant array sizes (#4700) | 
 |     - spirv-diff: Match OpSpecConstantComposite correctly (#4704) | 
 |     - spirv-diff: Use GetSingleWord*Operand (#4768) | 
 |     - spirv-diff: Basic support for OpTypeForwardPointer (#4761) | 
 |     - spirv-diff: Fix OpTypeFunction matching w.r.t operand count (#4771) | 
 |  | 
 | v2022.1 2022-01-26 | 
 |   - General | 
 |     - Add SPIR-V 1.6 support to wasm build (#4674) | 
 |     - Improvements to disassembly within PassManager (#4677) | 
 |     - Basic support for SPIR-V 1.6 (#4663) | 
 |     - reflect debug (#4662) | 
 |     - Fix endianness of string literals (#4622) | 
 |   - Optimizer | 
 |     - spirv-opt: add pass to Spread Volatile semantics (#4667) | 
 |     - Fix constant propagation and folding of FClamp instructions (#4651) | 
 |     - Manually fold floating point division by zero (#4637) | 
 |     - Allow ADCE to remove dead inputs (#4629) | 
 |   - Linker | 
 |     - Linker improvements (#4679) | 
 |       * test/linker: Code factorisation and small tweaks | 
 |       * linker: Do not fail when going over limits | 
 |   - Validator | 
 |     - val: interface struct with builtins must be Block (#4665) | 
 |   - Fuzzer | 
 |     - Avoid id bound errors during opt fuzzing (#4658) | 
 |     - Avoid uninitialised read when parsing hex float (#4646) | 
 |  | 
 | v2021.4 2021-11-11 | 
 |   - General | 
 |     - Add a WebAssembly build (#3752) | 
 |     - Make cxx exceptions controllable (#4591) | 
 |   - Validator | 
 |     - Improve decoration validation (#4490) | 
 |   - Optimizer | 
 |     - Add spirv-opt pass to replace descriptor accesses based on variable indices (#4574) | 
 |     - Do not fold snegate feeding sdiv (#4600) | 
 |     - Handle overflowing id in merge return (#4606) | 
 |   - Fuzzer | 
 |     - Add libFuzzer target for spirv-fuzz (#4434) | 
 |   - Linter | 
 |  | 
 | v2021.3 2021-08-24 | 
 |  - General | 
 |     - Initial support for SPV_KHR_integer_dot_product (#4327) | 
 |     - Add non-semantic vulkan extended instruction set (#4362) | 
 |     - Add common enum for debug info instructions from either opencl or vulkan (#4377) | 
 |  - Validator | 
 |     - Add validation for SPV_EXT_shader_atomic_float16_add (#4325) | 
 |     - Disallow loading a runtime-sized array (#4473) | 
 |     - spirv-val: Validate vulkan debug info similarly to opencl debug info (#4466) | 
 |  - Optimizer | 
 |     - spirv-opt: support SPV_EXT_shader_image_int64 (#4379) | 
 |     - spirv-opt: Add dataflow analysis framework (#4402) | 
 |     - Add control dependence analysis to opt (#4380) | 
 |     - Add spirv-opt convert-to-sampled-image pass (#4340) | 
 |     - spirv-opt: Add handling of vulkan debug info to DebugInfoManager (#4423) | 
 |  - Fuzz | 
 |     - spirv-fuzz: support AtomicLoad (#4330) | 
 |     - spirv-fuzz: Support AtomicStore (#4440) | 
 |     - spirv-fuzz: TransformationWrapVectorSynonym that rewrites scalar operations using vectors (#4376) | 
 |     - spirv-fuzz: Add minimal SPIR-V example to test shaders (#4415) | 
 |     - spirv-fuzz: support building using gn (#4365) | 
 |  - Linter | 
 |     - Add new target for spirv-lint (#4446) | 
 |     - spirv-lint: add basic CLI argument handling (#4478) | 
 |     - Add divergence analysis to linter (#4465) | 
 |  | 
 | v2021.2 2021-06-18 | 
 |  - General | 
 |     - Support SPV_KHR_subgroup_uniform_control_flow (#4318) | 
 |     - Support Intel extensions for fixed point and hls-float (#4321) | 
 |     - Fix crash when optimizing shaders with DebugPrintf (#4280) | 
 |  | 
 |  - Validator | 
 |     - Support Vulkan Storage Class for Execution Model (#4212) | 
 |  | 
 |  - Optimizer | 
 |     - Handle SPV_KHR_vulkan_memory_model in dead-code elimination (#4320) | 
 |     - Support folding OpBitcast with numeric constants (#4247) | 
 |  | 
 |  - Fuzz | 
 |     - Add tests for MaybeGet* functions in fuzzerutil (#4284) | 
 |     - Fix OutlineFunction in presence of unreachable blocks (#4308) | 
 |     - Fix def-use update in PermutePhiOperands (#4309) | 
 |     - Swap positions of two functions in a module (#4236) | 
 |  | 
 | v2021.1 2021-04-19 | 
 |  - General | 
 |     - Support SPV_KHR_linkonce_odr, SPV_KHR_expect_assume (#4161) | 
 |     - Fixes for the vscode language server extension (#4150) | 
 |  - Validator | 
 |     - Add validation for SPV_EXT_shader_atomic_float_min_max (#4105) | 
 |     - Add Vulkan Execution Scope checks (#4183) | 
 |     - Vulkan 64-bit OpAtomicStore check (#4163) | 
 |  - Optimizer | 
 |     - Add interpolate legalization pass (#4220) | 
 |  - Fuzz | 
 |     - Various performance optimizations | 
 |     - Do not add too many dead blocks (#4217) | 
 |     - Add WGSL compatibility flag to context (#4193) | 
 |     - Add persistent state to the fuzzer (#4137) | 
 |  | 
 | v2020.7 2021-02-16 | 
 |  - General | 
 |     - Support pending Intel extensions (#4116) | 
 |     - Remove WebGPU support (#4108) | 
 |  - Validator | 
 |     - Vulkan image gather constant component (#4133) | 
 |     - Add Vulkan PSB64 convert VUID (#4122) | 
 |     - Validate SPV_KHR_workgroup_memory_explicit_layout (#4128) | 
 |     - Validate VK_KHR_zero_initialize_workgroup_memory (#4124) | 
 |     - Add Vulkan image gather offset VUID (#4118) | 
 |     - Label Vulkan atomic semantics VUIDs (#4120) | 
 |     - Label VUID 04662 (#4123) | 
 |     - Label VUID 04683 (#4121) | 
 |     - Add Vulkan EXT builtins (#4115) | 
 |     - Validate Sampled=1 for Vulkan ImageQuerySizeLod, ImageQueryLevels, ImageQueryLod (#4103) | 
 |     - Add Vulkan Memory Scope VUs (#4106) | 
 |     - Add Vulkan Addressing Model check (#4107) | 
 |     - Vulkan atomic storage class (#4079) | 
 |     - Label standalone Vulkan VUID (#4091) | 
 |     - Add Vulkan decroation VUID (#4090) | 
 |     - Add Vulkan FP Mode VUID (#4088) | 
 |     - Fix Vulkan image sampled check (#4085) | 
 |     - Add Vulkan ForwardPointer VUID (#4089) | 
 |     - Add Vulkan ImageTexelPointer format check (#4087) | 
 |     - Add Vulkan Group Operation VUID (#4086) | 
 |     - Add first StandAlone VUID 04633 (#4077) | 
 |     - Add Subgroup VUIDs (#4074) | 
 |     - validate return type of OpImageRead (#4072) | 
 |     - tighter validation of multisampled images (#4059) | 
 |     - validate OpTypeImage Sampled values for environemnts (#4064) | 
 |     - validate StorageImageMultisampled capability (#4062) | 
 |     - Add last TessLevelOuter and TessLevelInner VUID (#4055) | 
 |     - Add last ClipDistance and CullDistance VUID (#4054) | 
 |     - Add last ViewportIndex and Layer VUID (#4053) | 
 |     - Add last Position VUID (#4052) | 
 |     - Allow forward pointer to be used in types generally (#4044) | 
 |  - Optimizer | 
 |     - Mark module as modified if convert-to-half removes decorations (#4127) | 
 |     - Fix binding number calculation in desc sroa (#4095) | 
 |     - Run DCE when SPV_KHR_shader_clock is used (#4049) | 
 |  - Debug Info | 
 |     - Set correct scope and line info for DebugValue (#4125) | 
 |     - Avoid integrity check failures caused by propagating line instructions (#4096) | 
 |  - Linker | 
 |     - Linker usability improvements (#4084) | 
 |  - Instrumentation | 
 |     - Generate differentiated error codes for buffer oob checking (#4097) | 
 |  - Fuzz | 
 |     - Fix OpPhi handling in DuplicateRegionWithSelection (#4065) | 
 |  | 
 | v2020.6 2020-12-07 | 
 |  - General | 
 |     CMake: Add SPIRV_TOOLS_BUILD_STATIC flag (#3910) | 
 |  - Disassembler | 
 |     Add some context comments to disassembly. (#3847) | 
 |  - Optimizer | 
 |    - Take new (raytracing) termination instructions into account. (#4050) | 
 |    - Do run DCE if SPV_KHR_ray_query is used. (#4047) | 
 |    - Handle 8-bit index in elim dead member (#4043) | 
 |    - Add texel buffer out-of-bounds checking instrumentation (#4038) | 
 |    - Update MeshShadingNV dependencies (and land Ray tracing updates) (#4028) | 
 |    - Fix buffer oob instrumentation for matrix refs (#4025) | 
 |    - Fix SSA re-writing in the presence of variable pointers. (#4010) | 
 |    - Add support to prevent functions from being inlined if they have | 
 |      DontInline flag (#3858) | 
 |    - Add SPV_EXT_shader_image_int64 (#3852) | 
 |    - Support SPV_KHR_fragment_shading_rate (#3943) | 
 |    - Fix use-after-move in val/validate.cpp (#3848) | 
 |  - Debug Info | 
 |    - properly preserve DebugValue indexes operand (#4022) | 
 |    - Add DebugValue for invisible store in single_store_elim (#4002) | 
 |    - Propagate OpLine to all applied instructions in spirv-opt (#3951) | 
 |    - Add DebugValue for DebugDecl invisible to value assignment (#3973) | 
 |    - Add DebugValue for function param regardless of scope (#3923) | 
 |    - Debug info preservation in convert-local-access-chains pass (#3835) | 
 |    - Debug info preservation in redundancy-elimination pass (#3839) | 
 |    - Debug info preservation in if-conversion pass (#3861) | 
 |  - Validator | 
 |    - Add validation support for the ray tracing built-in variables (#4041) | 
 |    - Use less stack space when validating Vulkan builtins (#4019) | 
 |    - Fix SPV_KHR_fragment_shading_rate VUID label (#4014) | 
 |    - Label Layer and ViewportIndex VUIDs (#4013) | 
 |    - Allow the ViewportIndex and Layer built-ins on SPIR-V 1.5 (#3986) | 
 |    - Fix validation of OpPhi instructions (#3919) | 
 |  - Fuzz | 
 |    - Fix facts arising from CompositeConstruct (#4034) | 
 |    - Do not flatten conditionals that create synonyms (#4030) | 
 |    - Add support for reining in rogue fuzzer passes (#3987) | 
 |    - Fix assertion failure in FuzzerPassAddCompositeExtract (#3995) | 
 |    - Fix invalid equation facts (#4009) | 
 |    - Fix bugs in TransformationFlattenConditionalBranch (#4006) | 
 |    - Fix bug related to transformation applicability (#3990) | 
 |    - Add expand vector reduction transformation (#3869) | 
 |    - Add FuzzerPassAddCompositeExtract (#3904) | 
 |    - Fix mismatch with shrinker step limit (#3985) | 
 |    - Fix off-by-one error in replayer (#3982) | 
 |    - Get order right for OpSelect arguments (#3974) | 
 |    - Do not add synonym-creating loops in dead blocks (#3975) | 
 |    - Skip OpTypeSampledImage when propagating up (#3976) | 
 |    - Pass OpUndef in function call if needed (#3978) | 
 |    - Fix off-by-one in TransformationCompositeConstruct (#3979) | 
 |    - Tolerate absent ids in data synonym fact management (#3966) | 
 |    - Fix to id availability (#3971) | 
 |    - Fix operand types (#3962) | 
 |    - Don't flatten conditional if condition is irrelevant (#3944) | 
 |    - Do not produce OpPhis of type OpTypeSampledImage (#3964) | 
 |    - Restrict fuzzer pass to reachable blocks (#3970) | 
 |    - Handle more types when extending OpPhi instructions (#3969) | 
 |    - Skip early terminator wrappers when merging returns (#3968) | 
 |    - Avoid irrelevant constants in synonym-creating loops (#3967) | 
 |    - Skip dead blocks in FuzzerPassAddOpPhiSynonyms (#3965) | 
 |    - Avoid the type manager when looking for struct types (#3963) | 
 |    - Fix to TransformationDuplicateRegionWithSelection (#3941) | 
 |    - Skip OpFunction when replacing irrelevant ids (#3932) | 
 |    - Use component-wise selectors when flattening conditional branches (#3921) | 
 |    - Avoid void struct member when outlining functions (#3936) | 
 |    - Do not allow Block-decorated structs when adding parameters (#3931) | 
 |    - Fix to operand id type (#3937) | 
 |    - Handle dead blocks in TransformationEquationInstruction (#3933) | 
 |    - Do not allow sampled image load when flattening conditionals (#3930) | 
 |    - Take care of OpPhi instructions when inlining (#3939) | 
 |    - Fix to TransformationInlineFunction (#3913) | 
 |    - Wrap early terminators before merging returns (#3925) | 
 |    - Lower probability of adding bit instruction synonyms (#3917) | 
 |    - Fix handling of OpPhi in FlattenConditionalBranch (#3916) | 
 |    - Avoid creating blocks without parents (#3908) | 
 |    - Do not allow creation of constants of block-decorated structs (#3903) | 
 |    - Fixes related to irrelevant ids (#3901) | 
 |    - Fix to transformation that adds a synonym via a loop (#3898) | 
 |    - Fix to duplicate region with selection (#3896) | 
 |    - Do not expose synonym facts for non-existent ids (#3891) | 
 |    - Do not add synonyms involving irrelevant ids (#3890) | 
 |    - Do not replace irrelevant ids that are not in blocks (#3892) | 
 |    - Wrap OpKill and similar in function calls (#3884) | 
 |    - Integrate spirv-reduce with shrinker (#3849) | 
 |    - Report fresh ids in transformations (#3856) | 
 |    - Support OpNot bit instruction case (#3841) | 
 |    - Return IR and transformation context after replay (#3846) | 
 |  | 
 | v2020.5 2020-09-22 | 
 |  - General | 
 |    - Enable building with BUILD_SHARED_LIBS=1 (#3490) | 
 |    - Avoid using /MP4 for clang on windows. (#3662) | 
 |    - Fix compiler error on macOS with XCode12. (#3836) | 
 |  - Optimizer | 
 |    - Preserve OpenCL.DebugInfo.100 through private-to-local pass (#3571) | 
 |    - Preserve debug info in scalar replacement pass (#3461) | 
 |    - Debug info preservation in loop-unroll pass (#3548) | 
 |    - Preserve debug info in dead-insert-elim pass (#3652) | 
 |    - Improve non-semantic instruction handling in the optimizer (#3693) | 
 |    - Let ADCE pass check DebugScope (#3703) | 
 |    - Add undef for inlined void function (#3720) | 
 |    - Fix SSA-rewrite to remove DebugDeclare for variables without loads (#3719) | 
 |    - Handle DebugScope in compact-ids pass (#3724) | 
 |    - Add buffer oob check to bindless instrumentation (#3800) | 
 |  - Validator | 
 |    - Update OpenCL capabilities validation (#3149) | 
 |    - Validator support for non-semantic clspv reflection (#3618) | 
 |    - OpenCL.DebugInfo.100 DebugTypeArray with variable size (#3549) | 
 |    - Only validation locations for appropriate execution models (#3656) | 
 |    - Validate more OpenCL.DebugInfo.100 instructions (#3684) | 
 |    - Allow DebugTypeTemplate for Type operand (#3702) | 
 |    - spirv-val: Add Vulkan VUID labels to BuiltIn (#3756) | 
 |    - Allow SPV_KHR_8bit_storage extension. (#3780) | 
 |    - Validate SPIRV Version number when parsing binary header (#3834) | 
 |  - Reduce | 
 |    - Support reducing a specific function (#3774) | 
 |  - Fuzz | 
 |    - adds TransformationReplaceCopyObjectWithStoreLoad (#3567) | 
 |    - adds TransformationReplaceCopyMemoryWithLoadStore (#3575) | 
 |    - adds TransformationReplaceLoadStoreWithCopyMemory (#3586) | 
 |    - Implement the OpOuterProduct linear algebra case (#3617) | 
 |    - Pass to replace int operands with ints of opposite signedness (#3612) | 
 |    - TransformationMoveInstructionDown (#3477) | 
 |    - Add TransformationMakeVectorOperationDynamic (#3597) | 
 |    - TransformationReplaceAddSubMulWithCarryingExtended (#3598) | 
 |    - FuzzerPassPropagateInstructionsUp (#3478) | 
 |    - add FuzzerPassAddCompositeInserts (#3606) | 
 |    - Add inline function transformation (#3517) | 
 |    - Transformation to replace the use of an irrelevant id (#3697) | 
 |    - Add SPIRV_FUZZ_PROTOC_COMMAND (#3789) | 
 |    - Add TransformationDuplicateRegionWithSelection (#3773) | 
 |    - Transformation to flatten conditional branch (#3667) | 
 |    - Handle OpPhis in TransformationInlineFunction (#3833) | 
 |    - Create synonym of int constant using a loop (#3790) | 
 |    - Support dead blocks in TransformationAddSynonym (#3832) | 
 |  - Linker | 
 |  | 
 | v2020.4 2020-07-22 | 
 |  - General | 
 |    - Changed variable names to be more descriptive (#3433) | 
 |    - Add support to GPU-AV instrumentation for Task and Mesh shaders (#3512) | 
 |    - Permit Simple and GLSL450 memory model in WEBGPU_0 (#3463) | 
 |    - Support SPV_KHR_terminate_invocation (#3568) | 
 |  - Optimizer | 
 |    - Preserving debug information in optimizations | 
 |      (#3389,#3420,#3425,#3356,#3459,#3444,#3492,#3451,#3497i,#3498,#3542) | 
 |    - Eliminate branches with condition of OpConstantNull (#3438) | 
 |    - Use structured order to unroll loops. (#3443) | 
 |    - Updated desc_sroa to support flattening structures (#3448) | 
 |    - Support OpCompositeExtract pattern in desc_sroa (#3456) | 
 |    - Fix ADCE pass bug for mulitple entries (#3470) | 
 |      - Sink pointer instructions in merge return (#3569) | 
 |  - Validator | 
 |    - Validate location assignments (#3308) | 
 |      - Fix reachability in the validator (#3541) | 
 |  - Reduce | 
 |  - Fuzz | 
 |    - Add support for OpSpecConstant* (#3373) | 
 |    - Add replace linear algebra instruction transformation (#3402) | 
 |    - Implement vector shuffle fuzzer pass (#3412) | 
 |    - Swap operands in OpBranchConditional (#3423) | 
 |    - Permute OpPhi instruction operands (#3421) | 
 |    - Add FuzzerPassAddCopyMemoryInstructions (#3391) | 
 |    - TransformationInvertComparisonOperator (#3475) | 
 |    - Add variables with workgroup storage class (#3485) | 
 |    - Add image sample unused components transformation (#3439) | 
 |    - TransformationReplaceParameterWithGlobal (#3434) | 
 |      - Support adding dead break from back-edge block (#3519) | 
 |        - Fuzzer pass to interchange zero-like constants (#3524) | 
 |  - Linker | 
 |  | 
 | v2020.3 2020-05-27 | 
 |  - General | 
 |    - Prevent Effcee from installing things when building spirv-tools with testing enabled (#3256) | 
 |    - Update acorn version (#3294) | 
 |    - If SPIRV-Headers is in our tree, include it as subproject (#3299) | 
 |    - allow cross compiling for Windows Store, UWP, etc. (#3330) | 
 |  - Optimizer | 
 |    - Remove deprecated interfaces from instrument passes (#3361) | 
 |    - Preserve debug info in inline pass (#3349) | 
 |    - Handle more cases in dead member elim (#3289) | 
 |    - Preserve debug info in eliminate-dead-functions (#3251) | 
 |    - Fix Struct CFG analysis for single block loop (#3293) | 
 |    - Add tests for recently added command line option (#3297) | 
 |    - Consider sampled images as read-only storage (#3295) | 
 |    - Allow various validation options to be passed to spirv-opt (#3314) | 
 |    - Add debug information analysis (#3305) | 
 |    - Preserve debug info for wrap-opkill (#3331) | 
 |    - refactor inlining pass (#3328) | 
 |    - Add unrolling to performance passes (#3082) | 
 |  - Validator | 
 |    - Add validation support for ImageGatherBiasLodAMD (#3363) | 
 |    - Validate ShaderCallKHR memory scope (#3332) | 
 |    - Validate Buffer and BufferBlock apply only to struct types (#3259) | 
 |  - Reduce | 
 |    - increase default step limit (#3327) | 
 |    - Remove unused uniforms and similar (#3321) | 
 |  - Fuzz | 
 |    - Add support for StorageBuffer (#3348) | 
 |    - Add validator options (#3254) | 
 |    - Limit adding of new variables to 'basic' types (#3257) | 
 |    - Transformation to add OpConstantNull (#3273) | 
 |    - Handling of more fuzzing opportunities (#3277, #3280, #3281, #3290, #3292) | 
 |    - Respect rules for OpSampledImage (#3287) | 
 |    - Do not outline regions that produce pointer outputs (#3291) | 
 |  - Linker | 
 |  | 
 | v2020.2 2020-03-26 | 
 |  - General: | 
 |    - Support extended instructions in the vscode language server | 
 |    - Make spvOpcodeString part of the public API (#3174) | 
 |    - Added guide to writing a spirv-fuzz fuzzer pass (#3190) | 
 |    - Add support for KHR_ray_{query,tracing} extensions (#3235) | 
 |  - Optimizer | 
 |    - Debug Printf support (#3215) | 
 |    - Add data structure for DebugScope, DebugDeclare in spirv-opt (#3183) | 
 |    - Fix identification of Vulkan images and buffers (#3253) | 
 |  - Validator | 
 |    - Add support for SPV_AMD_shader_image_load_store_lod (#3186) | 
 |    - Add validation rules for OpenCL.DebugInfo.100 extension (#3133) | 
 |    - Adding WebGPU specific Workgroup scope rule (#3204) | 
 |    - Disallow phis of images, samplers and sampled images (#3246) | 
 |  - Reduce | 
 |  - Fuzz | 
 |    - Fuzzer passes to add local and global variables (#3175) | 
 |    - Add fuzzer passes to add loads/stores (#3176) | 
 |    - Fuzzer pass to add function calls (#3178) | 
 |    - Fuzzer pass that adds access chains (#3182) | 
 |    - Fuzzer pass to add equation instructions (#3202) | 
 |    - Add swap commutable operands transformation (#3205) | 
 |    - Add fuzzer pass to permute function parameters (#3212) | 
 |    - Allow OpPhi operand to be replaced with a composite synonym (#3221) | 
 |  - Linker | 
 |  | 
 | v2020.1 2020-02-03 | 
 |  - General: | 
 |    - Add support for SPV_KHR_non_semantic_info (#3110) | 
 |    - Support OpenCL.DebugInfo.100 extended instruction set (#3080) | 
 |    - Added support for Vulkan 1.2 | 
 |    - Add API function to better handle getting the necessary environment (#3142) | 
 |    - Clarify mapping of target env to SPIR-V version (#3150) | 
 |    - Implement constant folding for many transcendentals (#3166) | 
 |  - Optimizer | 
 |    - Change default version for CreatInstBindlessCheckPass to 2 (#3096, #3119) | 
 |    - Better handling of OpLine on merge blocks (#3130) | 
 |    - Use placeholder switch instead of placeholder loop in MergeReturn pass. (#3151) | 
 |    - Handle TimeAMD in AmdExtensionToKhrPass. (#3168) | 
 |  - Validator | 
 |    - Fix structured exit validation (#3141) | 
 |  - Reduce | 
 |  - Fuzz | 
 |    - Fuzzer pass to merge blocks (#3097) | 
 |    - Transformation to add a new function to a module (#3114) | 
 |    - Add fuzzer pass to perform module donation (#3117) | 
 |    - Fuzzer passes to create and branch to new dead blocks (#3135) | 
 |    - Fuzzer pass to add composite types (#3171) | 
 |  - Linker: | 
 |    - Remove names and decorations of imported symbols (#3081) | 
 |  | 
 | v2019.5 2019-12-11 | 
 |  - General: | 
 |    - Export SPIRV-Tools targets on installation | 
 |    - SPIRV-Tools support for SPIR-V 1.5 (#2865) | 
 |    - Add WebGPU SPIR-V Assembler in JavaScript. (#2876) | 
 |    - Add Bazel build configuration. (#2891) | 
 |    - Add support for building with emscripten (#2948) | 
 |    - Update SPIR-V binary header test for SPIR-V 1.5 (#2967) | 
 |    - Add fuzzer for spirv-as call path (#2976) | 
 |    - Improved CMake install step. (#2963) | 
 |    - Add fuzzer for spirv-dis call path (#2977) | 
 |    - Ensure timestamp does not vary with timezone. (#2982) | 
 |    - Add a vscode extension for SPIR-V disassembly files (#2987) | 
 |    - Add iOS as a supported platform (#3001) | 
 |    - utils/vscode: Add SPIR-V language server support | 
 |    - Respect CMAKE_INSTALL_LIBDIR in installed CMake files (#3054) | 
 |    - Permit the debug instructions in WebGPU SPIR-V (#3063) | 
 |    - Add support for Fuchsia. (#3062) | 
 |  - Optimizer | 
 |    - Add descriptor array scalar replacement (#2742) | 
 |    - Add pass to wrap OpKill in a function call (#2790) | 
 |    - Fold FMix during constant folding. (#2818) | 
 |    - Add pass to replace AMD shader ballot extension (#2811) | 
 |    - Add pass to make Float32 operation relax precision (#2808) | 
 |    - Add pass to make relax precision operation Float16 (#2808) | 
 |    - Add pass to replace uses of 3 AMD extensions (#2814) | 
 |    - Fold Min, Max, and Clamp instructions. (#2836) | 
 |    - Better handling of OpKill in continues (#2842,#2922,#2933) | 
 |    - Enable OpTypeCooperativeMatrix specialization (#2927) | 
 |    - Support constant-folding UConvert and SConvert (#2960) | 
 |    - Update Offset to ConstOffset bitmask if operand is constant. (#3024) | 
 |    - Improve RegisterSizePasses (#3059) | 
 |    - Folding: perform add and sub on mismatched integer types (#3084) | 
 |    - Graphics robust access: use signed clamp (#3073) | 
 |    Fixes: | 
 |    - Instrument: Fix version 2 output record write for tess eval shaders. (#2782) | 
 |    - Instrument: Add support for Buffer Device Address extension (#2792) | 
 |    - Fix check for changed binary in API call. (#2798) | 
 |    - For WebGPU<->Vulkan optimization, set correct execution environment (#2834) | 
 |    - Handle OpConstantNull in copy-prop-arrays. (#2870) | 
 |    - Use OpReturn* in wrap-opkill (#2886) | 
 |  - Validator | 
 |    - Add generic builtin validation of target (#2843) | 
 |    - Extra resource interface validation (#2864) | 
 |    - Adding valilidation checks for OpEntryPoint duplicate names and execution mode (#2862) | 
 |    - Relaxed bitcast with pointers (#2878) | 
 |    - Validate physical storage buffer restrictions (#2930) | 
 |    - Add SPV_KHR_shader_clock validation (#2879, #3013) | 
 |    - Validate that selections are structured (#2962) | 
 |    - Disallow use of OpCompositeExtract/OpCompositeInsert with no indices (#2980) | 
 |    - Check that derivatives operate on 32-bit values (#2983) | 
 |    - Validate array stride does not cause overlap (#3028) | 
 |    - Validate nested constructs (#3068) | 
 |    Fixes: | 
 |    - Fix validation of constant matrices (#2794) | 
 |    - Update "remquor" validation | 
 |    - Only allow previously declared forward refs in structs (#2920) | 
 |  - Reduce | 
 |    - Remove relaxed precision decorations (#2797) | 
 |    - Reduce/fuzz: improve command line args (#2932) | 
 |    - Improve remove unref instr pass (#2945) | 
 |    Fixes: | 
 |  - Fuzz | 
 |    - Fix add-dead-break and add-dead-continue passes to respect dominance (#2838) | 
 |    - Add fuzzer pass to copy objects (#2853) | 
 |    - Add fuzzer pass to replace ids with synonyms (#2857) | 
 |    - Allow validation during spirv-fuzz replay (#2873) | 
 |    - Employ the "swarm testing" idea in spirv-fuzz (#2890) | 
 |    - reduce/fuzz: improve command line args (#2932) | 
 |    - option to convert shader into a form that renders red (#2934) | 
 |    - Add fuzzer pass to change selection controls (#2944) | 
 |    - add transformation and pass to construct composites (#2941) | 
 |    - Add fuzzer pass to change loop controls (#2949) | 
 |    - Add fuzzer pass to change function controls (#2951) | 
 |    - Add fuzzer pass to add NoContraction decorations (#2950) | 
 |    - Add missing functionality for matrix composites (#2974) | 
 |    - Fuzzer pass to adjust memory access operands (#2968) | 
 |    - Transformation to extract from a composite object (#2991) | 
 |    - Vector shuffle transformation (#3015) | 
 |    - Improve debugging facilities (#3074) | 
 |    - Function outlining fuzzer pass (#3078) | 
 |  | 
 |  | 
 | v2019.4 2019-08-08 | 
 |  - General: | 
 |    - Memory model support for SPIR-V 1.4 | 
 |    - Add new spirv-fuzz tool | 
 |    - Add option for base branch in check_code_format.sh | 
 |    - Removed MarkV and Stats code. (#2576) | 
 |    - Instrument: Add version 2 of record formats (#2630) | 
 |    - Linker: Better type comparison for OpTypeArray and OpTypeForwardPointer (#2580) | 
 |  - Optimizer | 
 |    - Bindless Validation: Instrument descriptor-based loads and stores (#2583) | 
 |    - Better folding for OpSpecConstantOp (#2585, #2614) | 
 |    - Add in individual flags for Vulkan <-> WebGPU passes (#2615) | 
 |    - Handle nested breaks from switches. (#2624) | 
 |    - Optimizer: Handle array type with OpSpecConstantOp length (#2652) | 
 |    - Perform merge return with single return in loop. (#2714) | 
 |    - Add --preserve-bindings and --preserve-spec-constants (#2693) | 
 |    - Remove Common Uniform Elimination Pass (#2731) | 
 |    - Allow ray tracing shaders in inst bindle check pass. (#2733) | 
 |    - Add pass to inject code for robust-buffer-access semantics (#2771) | 
 |    - Treat access chain indexes as signed in SROA (#2776) | 
 |    - Handle RelaxedPrecision in SROA (#2788) | 
 |    - Add descriptor array scalar replacement (#2742) | 
 |    Fixes: | 
 |    - Handle decorations better in some optimizations (#2716) | 
 |    - Change the order branches are simplified in dead branch elim (#2728) | 
 |    - Fix bug in merge return (#2734) | 
 |    - SSA rewriter: Don't use trivial phis (#2757) | 
 |    - Record correct dominators in merge return (#2760) | 
 |    - Process OpDecorateId in ADCE (#2761) | 
 |    - Fix check for unreachable blocks in merge-return (#2762) | 
 |    - Handle out-of-bounds scalar replacements. (#2767) | 
 |    - Don't move debug or decorations when folding (#2772) | 
 |    - Protect against out-of-bounds references when folding OpCompositeExtract (#2774) | 
 |  - Validator | 
 |    - Validate loop merge (#2579) | 
 |    - Validate construct exits (#2459) | 
 |    - Validate OpenCL memory and addressing model environment rules (#2589) | 
 |    - Validate OpenCL environment rules for OpTypeImage (#2606) | 
 |    - Allow breaks to switch merge from nested construct (#2604) | 
 |    - Validate OpenCL environment rules for OpImageWrite (#2619) | 
 |    - Allow arrays of out per-primitive builtins for mesh shaders (#2617) | 
 |    - Validate OpenCL rules for ImageRead and OpImageSampleExplicitLod (#2643) | 
 |    - Add validation for SPV_EXT_fragment_shader_interlock (#2650) | 
 |    - Add builtin validation for SPV_NV_shader_sm_builtins (#2656) | 
 |    - Add validation for Subgroup builtins (#2637) | 
 |    - Validate variable initializer type (#2668) | 
 |    - Disallow stores to UBOs (#2651)A | 
 |    - Validate Volatile memory semantics bit (#2672) | 
 |    - Basic validation for Component decorations (#2679) | 
 |    - Validate that in OpenGL env block variables have Binding (#2685) | 
 |    - Validate usage of 8- and 16-bit types with only storage capabilities (#2704) | 
 |    - Add validation for SPV_EXT_demote_to_helper_invocation (#2707) | 
 |    - Extra small storage validation (#2732) | 
 |    - For Vulkan, disallow structures containing opaque types (#2546) | 
 |    - Validate storage class OpenCL environment rules for atomics (#2750) | 
 |    - Update OpControlBarriers rules for WebGPU (#2769) | 
 |    - Update OpMemoryBarriers rules for WebGPU (#2775) | 
 |    - Update WebGPU validation rules of OpAtomic*s (#2777) | 
 |    Fixes: | 
 |    - Disallow merge targeting block with OpLoopMerge (#2610) | 
 |    - Update vloadn and vstoren validation to match the OpenCL Extended | 
 |      Instruction Set Specification (#2599) | 
 |    - Update memory scope rules for WebGPU (#2725) | 
 |    - Allow LOD ops in compute shaders with derivative group execution modes (#2752) | 
 |  - Reduce | 
 |    Fixes: | 
 |  | 
 | v2019.3 2019-05-14 | 
 |  - General: | 
 |    - Require Python 3 since Python 2 will out of service soon. | 
 |    - Add a continuous test that does memory checks using the address sanitizer. | 
 |    - Fix the build files so the SPIRV_USE_SANITIZER=address build works. | 
 |    - Packaging top of tree build artifacts again. | 
 |    - Added support for SPIR-V 1.4. (#2550) | 
 |  - Optimizer | 
 |    - Remove duplicates from list of interface IDs in OpEntryPoint instruction (#2449) | 
 |    - Bindless Validation: Descriptor Initialization Check (#2419) | 
 |    - Add option to validate after each pass (#2462) | 
 |    - Add legalization pass to fix mismatched pointer (#2430, #2535) | 
 |    - Add error messages when the input contains unknown instructions. (#2487) | 
 |    - Add pass to convert from WebGPU Spir-V to Vulkan Spir-V and back. (#2495) | 
 |    Fixes: | 
 |    - #2412: Dead memeber elimination should not change input and output variables. | 
 |    - #2405: Fix OpDot folding of half float vectors. | 
 |    - #2391: Dead branch elim should not fold away back edges. | 
 |    - #2441: Removing decorations when doing constant propagation. | 
 |    - #2455: Maintain inst to block mapping in merge return. | 
 |    - #2453: Fix merge return in the face of breaks. | 
 |    - #2456: Handle dead infinite loops in DCE. | 
 |    - #2458: Handle variable pointer in some optimizations. | 
 |    - #2452: Fix dead branch elimination to handle unreachable blocks better. | 
 |    - #2528: Fix undefined bit shift in sroa. | 
 |    - #2539: Change implementation of post order CFG traversal. | 
 |  - Validator | 
 |    - Add validation of storage classes for WebGPU (#2446) | 
 |    - Add validation for ExecutionMode in WebGPU (#2443) | 
 |    - Implement WebGPU specific CFG validation (#2386) | 
 |    - Allow NonWritable to target struct members. (#2420) | 
 |    - Allow storage type mismatch for parameter in relaxed addressing mode. | 
 |    - Allow non memory objects as parameter in relaxed addressing mode. | 
 |    - Disallow nested Blocks and buffer blocks (#2410). | 
 |    - Add validation for SPV_NV_cooperative_matrix (#2404) | 
 |    - Add --strip-atomic-counter-memory (#2413) | 
 |    - Check OpSampledImage is only passed into valid instructions (#2467) | 
 |    - Handle function decls in Structured CFG analysis (#2474) | 
 |    - Validate that OpUnreacahble is not statically reachable (#2473) | 
 |    - Add pass to generate needed initializers for WebGPU (#2481) | 
 |    - Allow images without format for OpenCL. (#2470) | 
 |    - Remove unreachable block validation (#2525) | 
 |    - Reduce runtime of array layout checks (#2534) | 
 |    - Add validation specific to OpExecutionModeId (#2536) | 
 |    - Validate sign of int types. (#2549) | 
 |    - VK_KHR_uniform_buffer_standard_layout validation (#2562) | 
 |    Fixes: | 
 |    - #2439: Add missing DepthGreater case to Fragment only check. | 
 |    - #2168: Disallow BufferBlock on StorageBuffer variables for Vulkan. | 
 |    - #2408: Restrict and Aliased decorations cannot be applied to the same id. | 
 |    - #2447: Improve function call parameter check. | 
 |  - Reduce | 
 |    - Add Pass to remove unreferenced blocks. (#2398) | 
 |    - Allows passing options to the validator. (#2401) | 
 |    - Improve reducer algorithm and other changes (#2472) | 
 |    - Add Pass to remove selections (#2485) | 
 |    - Add passes to simplify branches (#2507) | 
 |    Fixes: | 
 |    - #2478: fix loop to selection pass for loops with combined header/continue block | 
 |  | 
 | v2019.2 2019-02-20 | 
 |  - General: | 
 |    - Support SPV_EXT_physical_storage_buffer | 
 |    - A number of memory leak have been fixed. | 
 |    - Removed use of deprecated Google test macro: | 
 |    - Changed the BUILD.gn to only build tests in Chromium. | 
 |  - Optimizer | 
 |    - Upgrade memory model improvments for modf and frexp. | 
 |    - Add a new pass to move loads closer to their uses: code sinking. | 
 |    - Invalidating the type manager now invalidates the constnat manager. | 
 |    - Expand instrumentation pass for bindless bounds checking to runtime-sized descriptor arrays. | 
 |    - Add a new pass that removes members from structs that are not used: dead member elimination. | 
 |    Fixes: | 
 |    - #2292: Remove undefined behaviour when folding bit shifts. | 
 |    - #2294: Fixes for instrumentation code. | 
 |    - #2293: Fix overflow when folding -INT_MIN. | 
 |    - #2374: Don't merge unreachable blocks when merging blocks. | 
 |  - Validator | 
 |    - Support SPV_KHR_no_integer_wrap and related decorations. | 
 |    - Validate Vulkan rules for OpTypeRuntimeArray. | 
 |    - Validate NonWritable decoration. | 
 |    - Many WebGPU specific validation rules were added. | 
 |    - Validate variable pointer related function call rules. | 
 |    - Better error messages. | 
 |    Fixes: | 
 |    - #2307: Check forwards references in OpTypeArray. | 
 |    - #2315, #2303: Fixed the layout check for relaxed layout. | 
 |    - #1628: Emit an error when an OpSwitch target is not an OpLabel. | 
 |  - Reduce | 
 |    - Added more documentation for spirv-reduce. | 
 |    - Add ability to remove OpPhi instructions. | 
 |    - Add ability to merge two basic blocks. | 
 |    - Add ability to remove unused functions and unused basic blocks. | 
 |    Fixes: | 
 |  | 
 | v2019.1 2019-01-07 | 
 |  - General: | 
 |    - Created a new tool called spirv-reduce. | 
 |    - Add cmake option to turn off SPIRV_TIMER_ENABLED (#2103) | 
 |    - New optimization pass to update the memory model from GLSL450 to VulkanKHR. | 
 |    - Recognize OpTypeAccelerationStructureNV as a type instruction and ray tracing storage classes. | 
 |    - Fix GCC8 build. | 
 |    - Add --target-env flag to spirv-opt. | 
 |    - Add --webgpu-mode flag to run optimizations for webgpu. | 
 |    - The output disassembled line number stead of byte offset in validation errors. (#2091) | 
 |  - Optimizer | 
 |    - Added the instrumentation passes for bindless validation. | 
 |    - Added passes to help preserve OpLine information (#2027) | 
 |    - Add basic support for EXT_fragment_invocation_density (#2100) | 
 |    - Fix invalid OpPhi generated by merge-return. (#2172) | 
 |    - Constant and type manager have been turned into analysies. (#2251) | 
 |    Fixes: | 
 |    - #2018: Don't inline functions with a return in a structured CFG contstruct. | 
 |    - #2047: Fix bug in folding when volatile stores are present. | 
 |    - #2053: Fix check for when folding floating pointer values is allowed. | 
 |    - #2130: Don't inline recursive functions. | 
 |    - #2202: Handle multiple edges between two basic blocks in SSA-rewriter. | 
 |    - #2205: Don't unswitch a latch condition during loop unswitch. | 
 |    - #2245: Don't fold branch in loop unswitch.  Run dead branch elimination to fold them. | 
 |    - #2204: Fix eliminate common uniform to place OpPhi instructions correctly. | 
 |    - #2247: Fix type mismatches caused by scalar replacement. | 
 |    - #2248: Fix missing OpPhi after merge return. | 
 |    - #2211: After merge return, fix invalid continue target. | 
 |    - #2210: Fix loop invariant code motion to not place code between merge instruction and branch. | 
 |    - #2258: Handle CompositeInsert with no indices in VDCE. | 
 |    - #2261: Have replace load size handle extact with no index. | 
 |  - Validator | 
 |    - Changed the naming convention of outputing ids with names in diagnostic messages. | 
 |    - Added validation rules for UniformConstant variables in Vulkan. | 
 |    - #1949: Validate uniform variable type in Vulkan | 
 |    - Ensure for OpVariable that result type and storage class operand agree (#2052) | 
 |    - Validator: Support VK_EXT_scalar_block_layout | 
 |    - Added Vulkan memory model semantics validation | 
 |    - Added validation checkes spefic to WebGPU environment. | 
 |    - Add support for VK_EXT_Transform_feedback capabilities (#2088) | 
 |    - Add validation for OpArrayLength. (#2117) | 
 |    - Ensure that function parameter's type is not void (#2118) | 
 |    - Validate pointer variables (#2111) | 
 |    - Add check for QueueFamilyKHMR memory scope (#2144) | 
 |    - Validate PushConstants annotation and type (#2140) | 
 |    - Allow Float16/Int8 for Vulkan 1.0 (#2153) | 
 |    - Check binding annotations in resource variables (#2151, #2167) | 
 |    - Validate OpForwardPointer (#2156) | 
 |    - Validate operation for OpSpecConstantOp (#2260) | 
 |    Fixes: | 
 |    - #2049: Allow InstanceId for NV ray tracing | 
 |  - Reduce | 
 |    - Initial commit wit a few passes to reduce test cases. | 
 |    - Validation is run after each reduction step. | 
 |    Fixes: | 
 |  | 
 |  | 
 | v2018.6 2018-11-07 | 
 |  - General: | 
 |    - Added support for the Nvidia Turing and ray tracing extensions. | 
 |    - Make C++11 the CXX standard in CMakeLists.txt. | 
 |    - Enabled a parallel build for MSVC. | 
 |    - Enable pre-compiled headers for MSVC. | 
 |    - Added a code of conduct. | 
 |    - EFFCEE and RE2 are now required when build the tests. | 
 |  - Optimizer | 
 |    - Unrolling loops marked for unrolling in the legalization passes. | 
 |    - Improved the compile time of loop unrolling. | 
 |    - Changee merge-return to create a placeholder loop around the function. | 
 |    - Small improvement to merge-blocks to allow it to merge more often. | 
 |    - Enforce an upper bound for the ids, and add option to set it. | 
 |    - #1966: Report error if there are unreachable block before running merge return | 
 |    Fixes: | 
 |    - #1917: Allow 0 (meaning unlimited) as a parameter to --scalar-replacement | 
 |    - #1915: Improve handling of group decorations. | 
 |    - #1942: Fix incorrect uses of the constant manager.  Avoids type mismatches in generated code. | 
 |    - #1997: Fix dead branch elimination when there is a loop in folded selection. | 
 |    - #1991: Fixes legality check in if-conversion. | 
 |    - #1987: Add nullptr check to array copy propagation. | 
 |    - #1984: Better handling of OpUnreachable in ADCE. | 
 |    - #1983: Run merge return on reachable functions only. | 
 |    - #1956: Handled atomic operations in ADCE. | 
 |    - #1963: Fold integer divisions by 0 to 0. | 
 |    - #2019: Handle MemberDecorateStringGOOGLE in ADCE and strip reflect. | 
 |  - Validator | 
 |    - Added validation for OpGroupNonUniformBallotBitCount. | 
 |    - Added validation for the Vulkan memory model. | 
 |    - Added support for VK_KHR_shader_atddomic_int64. | 
 |    - Added validation for execution modes. | 
 |    - Added validation for runtime array layouts. | 
 |    - Added validation for 8-bit storage. | 
 |    - Added validation of OpPhi instructions with pointer result type. | 
 |    - Added checks for the Vulkan memory model. | 
 |    - Validate MakeTexelAvailableKHR and MakeTexelVisibleKHR | 
 |    - Allow atomic function pointer for OpenCL. | 
 |    - FPRounding mode checks were implemented. | 
 |    - Added validation for the id bound with an option to set the max id bound. | 
 |    Fixes: | 
 |    - #1882: Improve the validation of decorations to reduce memory usage. | 
 |    - #1891: Fix an potential infinite loop in dead-branch-elimination. | 
 |    - #1405: Validate the storage class of boolean objects. | 
 |    - #1880: Identify arrays of type void as invalid. | 
 |    - #487: Validate OpImageTexelPointer. | 
 |    - #1922: Validate OpPhi instructions are at the start of a block correctly. | 
 |    - #1923: Validate function scope variable are at the start of the entry block. | 
 |  | 
 | v2018.5 2018-09-07 | 
 |  - General: | 
 |    - Support SPV_KHR_vulkan_memory_model | 
 |    - Update Dim capabilities, to match SPIR-V 1.3 Rev 4 | 
 |    - Automated build bots no run tests for the VS2013 case | 
 |    - Support Chromium GN build | 
 |    - Use Kokoro bots: | 
 |      - Disable Travis-CI bots | 
 |      - Disable AppVeyor VisualStudio Release builds. Keep VS 2017 Debug build | 
 |    - Don't check export symbols on OSX (Darwin): some installations don't have 'objdump' | 
 |    - Reorganize source files and namespaces | 
 |    - Fixes for ClangTidy, and whitespace (passes 'git cl presumit --all -uf') | 
 |    - Fix unused param compile warnings/errors when Effcee not present | 
 |    - Avoid including time headers when timer functionality is disabled | 
 |    - Avoid too-stringent warnings flags for Clang on Windows | 
 |    - Internal refactoring | 
 |    - Add hooks for automated fuzzing | 
 |    - Add testing of command line executables | 
 |    - #1688: Use binary mode on stdin; fixes "spirv-dis <foo.spv" on Windows | 
 |  - Optimizer | 
 |    - The optimizer validates the module before it begins | 
 |    - Add API to register passes by string name | 
 |    - Fold a vector shuffle feeding a vector shuffle | 
 |    - Add -combine-access-chains transform | 
 |    - Refactor how IRContext is handled by passes | 
 |    - Improve bookkeeping for instruction result type and result id | 
 |    - Fix over-duplication of decorations | 
 |    - Fix handling of exits from selections in dead-branch elimination, and dead code | 
 |      elimination. | 
 |    - Fix handling of certain kinds of flow control in merge-return | 
 |    Fixes: | 
 |    - #1721: Fix size bug when folding vector shuffles | 
 |    - #1722: Fix size infinite loop when folding vector shuffles | 
 |    - #1724: Fix finding a constant of a specific type | 
 |    - #1727: Dead branch elim: Reorder blocks if needed to satisfy dominance rule | 
 |    - #1729: Handle VariablePointers cases in various optimizations | 
 |    - #1731: Fix vector shuffle with literal id indicating undef value | 
 |    - #1736: Fix handling of decorations and phis in merge-return | 
 |    - #1787: Fix handling of decorations related to access chains | 
 |    - #1865: Avoid leaking memory for SPIR-V constant values | 
 |  - Validator | 
 |    - Improve error messages | 
 |    - Avoid platform-dependent traversal ordering, to ensure consistent messages | 
 |    - Use libspirv::Instruction where possible | 
 |    - Add option to skip all block layout checks | 
 |    - Validate all type IDs | 
 |    - Validate uses of OpFunction | 
 |    - Validate uses of OpTypeFunction | 
 |    - Disallow a struct containing its own type https://crbug.com/874372 | 
 |    - #1685: Vulkan permits non-monotonic offsets for block members | 
 |    - #1697: Enforce block layout rules even when using relaxed block layout option | 
 |    - #1719: Fix line number for vector shuffle valiation error | 
 |    - #1789: Avoid assertion failure when validating some functions | 
 |    - #1800: Fix validation of OpCopyMemorySized | 
 |    - #1822: Stop enforcing struct member offset montonicity | 
 |    - #1831: Disallow void members in structs | 
 |  | 
 | v2018.4 2018-07-08 | 
 |  - General: | 
 |    - Support SPV_KHR_8bit_storage | 
 |    - Add gclient and presubmit configurations | 
 |    - Enable Kokoro build bots (#1625) | 
 |    - Group tests into fewer executables, reduces load on CI | 
 |    - Port test script to Python 3 | 
 |    - Symbol export tests respect SPIRV_SKIP_TESTS | 
 |    - #1596: Operand lookup succeeds if enabled by a capability | 
 |    - #1624: Instruction lookup succeeds if enabled by a capability | 
 |    - Refactoring namespaces: | 
 |      - #1678: Change libspirv to spvtools | 
 |      - Code in source/utils moved into spvtools::utils | 
 |      - Code in source/comp moved into spvtools::comp | 
 |  - Optimizer: | 
 |    - Remove insert-extract-elim pass. Use simplification pass instead. | 
 |    - Preserve instruction-to-block mapping in most passes, to reduce runtime. | 
 |    - Small vector optimization for operands | 
 |    - Add pass to move Private variables to Function. Increase opportunity to optimize. | 
 |    - Fixes: | 
 |      #1120: Check static uses of entry point interfaces | 
 |      #1372: Avoid merging some structs, to preserve names for reflection | 
 |      #1577: Scalar replacement uses only undecorated types. | 
 |      #1578: Fix handling of forward-pointer types, and types embedding pointers | 
 |        to themselves. | 
 |      #1591: Inliner: Callee variable with initializer should have a store at the call site. | 
 |      #1634: Fix crash: Use type id in vector type lookup | 
 |      #1649: Fix assert in compact-ids pass | 
 |      Fix constant folder: ensure it uses the right type | 
 |      #1659: Folding rules added to IRContext. Avoids leak. | 
 |  - Validator | 
 |    - Add work-in-progress WebGPU environment. Disallows OpUndef | 
 |    - #670, #1581: Improve error messages; disassemble instruction | 
 |    - #491: Check structured switches | 
 |    - #937: Check layout rules for Block and BufferBlock in Uniform, StorageBuffer, PushConstant | 
 |    - #1281: Check invalid branches into structured constructs | 
 |    - #1522: Disallow array-of-arrays with DescriptorSets | 
 |    - #1577: Allow duplicate pointer types. | 
 |    - #1581: Better messages: output ID names along with numbers in more cases. | 
 |    - #1597: Check Vulkan 1.1 capabilities | 
 |    - #1618: Check invalid exit from structured case construct | 
 |    - #1622: Run IdPass before DataRulesPass | 
 |    - #1632: Reduce test time by artificially lowering limits in limit test | 
 |    - #1638: Block-decorated structs member order must respect offset order | 
 |    - #1657: Improve CFG validation diagnostics | 
 |    - Khronos SPIR-V #337: GLSL.std.450 Refract instruction Eta param can be any float scalar. | 
 |    - #1606: PushConstant Blocks follow storage-buffer layout rules | 
 |    - #1664: Check layout of StorageBuffer variables with Block decoration, using storage buffer | 
 |      rules | 
 |    - #1666: Layout validation should permit {vec3; float} packing | 
 |    - #1637, #1668: Layout validation uses RowMajor, ArrayStride, MatrixStride properly | 
 |  - Linker | 
 |    - Avoid buffer overrun when creating OpModuleProcessed | 
 |  | 
 | v2018.3 2018-05-25 | 
 |  - General: | 
 |    - Support SPV_EXT_descriptor_indexing | 
 |    - Support SPV_GOOGLE_decorate_string | 
 |    - Support SPV_GOOGLE_hlsl_functionality1 | 
 |    - Support SPV_NV_shader_subgroup_partitioned | 
 |    - Use "unified1" grammar from SPIRV-Headers | 
 |    - Simplify support for new extensions. Assembler, disassembler, and simple validation | 
 |      support is automatic if new tokens are introduced with appropriate extension | 
 |      attributes in the "unified1" SPIR-V core grammar. | 
 |    - Disassembler: Emit more digits on floating point, to reliably reproduce all | 
 |      significand bits.  (Use std::max_digits10 instead of std::digits10) | 
 |    - Fix compilation for old XCode versions: Explicit construction required for std::set. | 
 |  - Optimizer: | 
 |    - Add --strip-reflect | 
 |    - Add --time-report | 
 |    - Add --loop-fission | 
 |    - Add lop fusion. | 
 |    - Add loop peeling pass and internal utility. | 
 |    - Improve optimizer runtime. | 
 |    - Merge-return now works with structured control flow. | 
 |    - New (faster) SSA rewriter to convert local loads and stores to SSA IDs and phis. | 
 |      Can replace load/store elimination passes. | 
 |    - Fix instruction folding case: insertion that feeds and extract, when the extract | 
 |      remains. | 
 |    - Fold OpDot. | 
 |    - Fold OpFNegate. | 
 |    - Fold multply and divide of same value. | 
 |    - Fold FClamp feeding a compare. | 
 |    - Fold OpLoad feeding an extract, to reduce excessive copying. (#1547) | 
 |    - Fold Fmix feeding an extract. | 
 |    - Use simplification pass instead of insert-extract elimination. | 
 |    - Constant fold OpVectorTimesScalar. | 
 |    - Copy propagate arrays, in simple cases. | 
 |    - Aggressive dead code elimination: Can remove more instructions, e.g. derivatives. | 
 |    - Aggressive dead code elimination: Remove Workgroup variables that are written but not read. | 
 |    - Better handling of OpImageTexelPointer | 
 |    - Initial utilities for scalar evolution. | 
 |    - Add Vector dead code elimination. | 
 |    - Each pass can only run once. | 
 |    - Allow code hosting in if-conversion. | 
 |    - Add external interface for adding a PassToken, so external code can make their own | 
 |      passes. | 
 |    - Fixes: | 
 |      #1404: Don't optimize away the compute compute workgroup size constant. | 
 |      #1407: Remove a bad assertion | 
 |      #1456: Fix bug in SSA rewriter related to variables updated in loops. | 
 |      #1487: Fix long runtime in Dead insertion elimination: Don't revist select phi nodes. | 
 |      #1492: Aggressive dead code elimination can remove OpDecorateStringGOOGLE. | 
 |      #1527: Fix inlining of functions having OpKill and OpUnreachable. | 
 |      #1559: Fix assert failure in reduce-load-size pass. | 
 |      #1556: Aggressive dead code elimination: Fix handling of OpCopyMemory. | 
 |  - Validator: | 
 |    - Check Vulkan built-in variables | 
 |    - Check Vulkan-specific atomic result type rule. | 
 |    - Relax control barrier check for SPIR-V 1.3.  Fixes #1427 | 
 |    - Check OpPhi. | 
 |    - Check OpMemoryModel. | 
 |    - Stop checking sizes derived from spec-constants. | 
 |    - Re-enable checks for OpUConvert. | 
 |    - Vulkan: Fix check for PrimitiveId: Permit as Input in fragment shader. | 
 |    - Validate binary version for the given target environment. | 
 |    - Add tests for OpBranch checks. | 
 |    - Vulkan 1.1: Check scope for non-uniform subgroup operations. | 
 |    - Fix checks for SPV_AMD_gpu_shader_int16. | 
 |    - Fix logical layout check for OpDecorateId. | 
 |    - Fix checks for ViewportIndex & Layer for Vulkan and SPV_EXT_shader_viewport_index_layer. | 
 |    - Fixes: | 
 |      #1470: Vulkan: Don't restrict WorkgroupSize to Input storage class. | 
 |      #1469: Vulkan: Permit Subgroup memory scope for Vulkan 1.1. | 
 |      #1472: Per-vertex variable validation fixes. | 
 |      #1483: Valdiate barrier execution scopes for Vulkan 1.1. | 
 |  - Fixes: | 
 |    #898: Linker properly removes FuncParamAttr from imported symbols. | 
 |    #924, #1174: Fix handling of decoration groups in optimizer, linker. | 
 |  | 
 | v2018.2 2018-03-07 | 
 |  - General: | 
 |    - Support SPIR-V 1.3 and Vulkan 1.1. | 
 |      - Default target environment is now SPIR-V 1.3.  For command-line tools, | 
 |        use the --target-env option to override the default.  Examples: | 
 | 	  # Generate a SPIR-V 1.0 binary instead of SPIR-V 1.3 | 
 | 	  spirv-as --target-env spv1.0 a.spvasm -o a.spv | 
 | 	  spirv-as --target-env vulkan1.0 a.spvasm -o a.spv | 
 | 	  # Validate as Vulkan 1.0 | 
 | 	  spirv-val --target-env vulkan1.0 a.spv | 
 |    - Support SPV_GOOGLE_decorate_string and SPV_GOOGLE_hlsl_functionality1 | 
 |  - Fixes: | 
 |    - Fix Android.mk build. Compilation was failing due to missing definitions of | 
 |      SpvCapabilityFloat16ImageAMD and other enumerated values. | 
 |    - Optimizer: Avoid generating duplicate names when merging types. | 
 |    - #1375: Validator: SPV_AMD_gpu_shaer_half_float implicitly allows declaration | 
 |      of the 16-bit floating point type. | 
 |    - #1376: Optimizer: Avoid folding half-precision float. | 
 |  | 
 | v2018.1 2018-03-02 | 
 |  - General: | 
 |    - Support Visual Studio 2013 again. (Continue support for VS 2015 and VS 2017.) | 
 |    - Support building SPIRV-Tools as a shared library. | 
 |    - Improve the HLSL legalization optimization recipe. #1311 | 
 |  - Optimizer: | 
 |    - General speedups. | 
 |    - Remove generic dead code elimination functionality from transforms: | 
 |        --eliminate-local-single-block | 
 |        --eliminate-local-single-store | 
 |        --eliminate-local-multi-store | 
 |      To recover the previous behaviour, a recipe using those transforms should now | 
 |      also invoke the --eliminate-dead-code-aggressive transform. | 
 |    - Improve folding, including coverage for floating point, OpSelect, and arithmetic | 
 |      with non-trivial constant operands. | 
 |    - Add loop-invariant code motion pass. | 
 |    - Add loop-unrolling pass, for honouring unroll hits. | 
 |    - Add loop-unswitch pass. | 
 |    - Add instruction simplification pass. | 
 |    - Aggressive dead code elimination: Understands capability hierarchy when finding | 
 |      instructions it can eliminate (combinators). (PR #1268) | 
 |    - CCP can now fold floating point arithmetic. #1311 | 
 |  - Validator: | 
 |    - Validate barrier instructions. | 
 |    - Check Vulkan-specific rules for atomics. | 
 |    - Check Vulkan prohibition of Location or Component decorations on BuiltIn variables. | 
 |  - Linker: | 
 |    - Add --verify-ids option | 
 |    - Add option to allow a resulting module to be partially linked. | 
 |    - Handle OpModuleProcessed (instructions in SPIR-V layout section 7c) | 
 |  - Fixes: | 
 |    - #1265: Optimizer: Fix use-after free bug in if-conversion. (Fix object lifecycle bug | 
 |      in type manager.) | 
 |    - #1282: Fix new warnings found by GCC 8.0.1. | 
 |    - #1285: Optimizer: Fix random failures during inlining.  (Dangling references in DefUseManager) | 
 |    - #1295: Optimizer: Fix incorrect handling of Phi nodes in CCP. | 
 |    - #1300: Fix CCP: avoid bad CCP transitions and unsettled values. | 
 |    - #1304: Avoid static-duration variables of class type (with constructors). | 
 |    - #1323: Fix folding of an insert composite feeding a composite extract. | 
 |    - #1339: Fix CCP: Handle OpConstantNull boolean values as conditions. | 
 |    - #1341: DCEInst: Keep atomic instructions (and some others with side effects). | 
 |    - #1354: Don't fold integer division. | 
 |    - #1357: Support OpConstantNull in folding. | 
 |    - #1361: CCP: Fix handling of non-constant module-scope values | 
 |  | 
 | v2018.0 2018-02-02 | 
 |  - General | 
 |    - VisualStudio 2013 is no longer supported.  VisualStudio 2015 is supported. | 
 |    - Use "include/unified1" directory from SPIRV-Headers.  Requires recent SPIRV-Headers source. | 
 |  - Disassembler: spirv-dis adds --color option to force color disassembly. | 
 |  - Optimizer: | 
 |    - Add pass to eliminate dead insertions. | 
 |    - Aggressive dead code elimination now removes OpSwitch constructs. | 
 |    - Block merging occurs in more cases. | 
 |    - Add driver workaround transform: replace OpUnreachable with harmless branch to merge. | 
 |    - Improve instruction folding framework. | 
 |    - Add loop analysis. | 
 |    - Add scalar replacement of aggregates to size-optimization recipe. | 
 |    - Add pass to replace instructions invalid for a shader stage, with a harmless value. | 
 |      This changes the semantics of the program!  Not for general use! | 
 |    - Rearragne and add passes to performance-optimization recipe, to produce better results. | 
 |  - Validator: | 
 |    - Validate OpenCL extended instructions. | 
 |    - Shaders can't perform atomics on floats. | 
 |    - Validate memory semantics values in atomics. | 
 |    - Validate instruction-adjacency constraints, e.g. OpPhi predecessors, merge instructions | 
 |      immediately precede branches. | 
 |  - Fixes: | 
 |    - PR 1198: Optimizer: Fix CCP in presence of matrix constants. | 
 |    - #1199: Optimizer: Fix CCP: don't propagate spec constants. | 
 |    - #1203: Optimizer: Fix common uniform elim bug introduced by refactoring. | 
 |    - #1210: Optimizer: Aggressive dead code elimination: Fix 'break' identification. | 
 |    - #1212: Optimizer: Aggressive dead code elimination: Was skipping too many instructions. | 
 |    - #1214: Optimizer: Aggressive dead code elimination: Fix infinite loop. | 
 |    - #1228: Optimizer: Fix CCP: Handling of varying Phi nodes; was resulting in infinite loop. | 
 |    - #1245: Optimizer: Dead branch elimination: Avoid a null pointer dereference. | 
 |    - #1250: Optimizer: Dead branch elimination: Avoid spuriously reporting a change. | 
 |  | 
 | v2017.3 2018-01-12 | 
 |  - General: | 
 |    - Support DebugInfo extended instruction set, targeted at OpenCL environments. | 
 |      See the SPIR-V Registry. | 
 |    - Generate a SPIRV-Tools.pc file for pkg-config. | 
 |  - Optimizer: | 
 |    - Progress for legalization of code generated from HLSL (issue #1118): | 
 |      - Add --legalize-hlsl option to run transforms used to transform intermediate | 
 |        code generated by HLSL to SPIR-V for Vulkan compilers.  Those compilers | 
 |        normally run these transforms automatically.  This option is used for developing | 
 |        those transforms. | 
 |      - Add Private-to-Function variable conversion for modules with logical | 
 |        addressing. | 
 |    - Add --ccp: SSA Conditional Constant Propagation (CCP) | 
 |    - Add --print-all to show disassembly for each optimization pass. | 
 |    - Internal: Add loop descriptors and post-order tree iterator. | 
 |    - Generalized dead branch elimination | 
 |    - Aggressive dead code elimination (ADCE) now removes dead functions and | 
 |      module-scope variables. | 
 |    - Vector extract/insert elimination now optimizes through some cases of | 
 |      VectorShuffle, and GLSL.std.450 Mix extended instruction. | 
 |  - Validator: | 
 |    - Add validation for GLSL.std.450 extended instruction set. | 
 |    - Check out of bounds composite accesses, where that's statically computable. | 
 |      Fixes #1112. | 
 |    - Check upper bits of literal numbers that aren't a multiple of 32-bits wide. | 
 |    - More validation of primitive instructions | 
 |    - Add optional "relaxed" checking logical addressing mode to permit some | 
 |      cases of pointer-to-pointer.  Contributes to HLSL legalization (issue #1118). | 
 |  - Fixes: | 
 |    #1100: Validator: Image operand Sample can be used with OpImageSparseFetch, | 
 |      OpImageSparseRead. | 
 |    #1108: Remove duplicates transform was incorrectly removing non-duplicate | 
 |      decorations. | 
 |    #1111: Optimizer's type manager could reference deleted memory. | 
 |    #1112: Fix decoration equality check, e.g. it is now symmetric. | 
 |    #1129: Validator now disallows Dim=SupbassData for OpImageSparseRead. | 
 |    #1143: Fix CCP: Was generating incorrect code for loops. | 
 |    #1153: Fix CCP crash. | 
 |    #1154: Optimizer's internal instruction-to-block mappings were sometimes | 
 |        inconsistent. | 
 |    #1159: Fix CCP infinite loop. | 
 |    #1168: Fix dead branch elimination intermittently generating incorrect code. | 
 |        Fixes https://github.com/KhronosGroup/glslang/issues/1205 | 
 |    #1186: Fix validation of PackDouble2x32 and UnpackDouble2x32 | 
 |  | 
 | v2017.2 2017-12-15 | 
 |  - General: | 
 |    - Support OpenCL 1.2, 2.0 target environments, including embedded profiles | 
 |    - Add CONTRIBUTING.md | 
 |    - Fix exit status code for spirv-link | 
 |    - Disassember: Enable emitting ANSI colour codes to a string | 
 |    - Library avoids polluting global namespace.  The libraries can export C and C++ | 
 |      symbols starting with "spv", or in a C++ namespace.  Add a test for this. | 
 |    - Linux release builds include debug information, for easier profiling | 
 |    - Build bots no longer test VisualStudio 2013 | 
 |      - Testing dependency RE2 requires VisualStudio 2015 or later | 
 |    - Build bots check code formatting | 
 |  - Optimizer: | 
 |    - Add --skip-validation to spirv-opt | 
 |    - Add dominance tree analysis | 
 |    - Add generic value propagation engine | 
 |    - Add global redundancy elimination within a function | 
 |    - Add scalar replacement of function-scope variables of composite type | 
 |    - Aggressive dead code elimination: Remove empty loops | 
 |    - Killing an instruction notifies the IRContext | 
 |    - IRContext::KillInst deletes the instruction | 
 |    - Move CFG analysis to IRContext | 
 |    - Add constant manager | 
 |    - Fix: Don't consider derivative instructions as combinators. | 
 |    - Fix: Don't delete an instruction twice in local dead-code-elimination | 
 |    - Fix: Don't consider derivative instructions as combinators. | 
 |  - Validator: | 
 |    - Finish checking of image instructions (Section 3.32.10) | 
 |      - Check sparse image instructions | 
 |      - Check OpTypeImage, OpTypeSampleImage | 
 |    - Check composite instructions (Section 3.32.12) | 
 |    - Check atomic instructions (Section 3.32.18) | 
 |    - Check OpEmitStreamVertex, OpEndStreamPrimitive instructions | 
 |    - Re-enable validation of OpCopyObject | 
 |    - OpKill, image ImplicitLod and QueryLod instructions can only be used in Fragment | 
 |      shaders. | 
 |    - Fixes for image instruction validation: | 
 |      - Lod image operand only usable with ExplicitLod and OpImageFetch | 
 |      - ExplicitLod Lod image operand must be float scalar | 
 |      - OpImageFectch Lod image operand must be int scalar | 
 |      - OpImageGather component operand must be 32-bits (integer scalar) | 
 |      - OpImageQuerySizeLod Lod must be integer scalar | 
 |  - Fixes: | 
 |    #622: Remove names and decorations when inlining | 
 |    #989: Aggressive dead code elim: Don't optimize away live breaks from a loop | 
 |    #991: Fix validation of SPV_AMD_shader_ballot | 
 |    #1004: Use after free of an instruction, in remove-duplicates transform | 
 |    #1007: OpImageRead not required to return 4-component vector | 
 |    #1009: OpImageRead can return scalar int/float types | 
 |    #1011: OpImageWrite should allow scalar int/float texel types | 
 |    #1012: Fix validat Dref type check | 
 |    #1017: Load-store elimination considers variable initializations | 
 |    #1034: Fix Windows debug build: operator< should be a weak ordering | 
 |    #1083: Inlining: Set parent (function) for each inlined basic block. | 
 |    #1075: Aggressive dead code elimination: Was leaving dangling references to | 
 |      removed blocks. | 
 |  | 
 | v2017.1 2017-11-23 | 
 |  - Update README with details on the public_spirv_tools_dev@khronos.org mailing list. | 
 |  - General: | 
 |    - Automatically deploy built artifacts to GitHub Releases | 
 |    - Add a Linker (module combiner). Under development. | 
 |    - Add Android.mk for Android NDK builds. | 
 |    - Add the 'effcee' library as an optional dependency for use in tests. | 
 |      Eventually it will be a required dependency, once downstream projects have | 
 |      a chance to adjust.  Requires 're2' library. | 
 |    - Avoid static-duration variables of class type (with constructors). | 
 |    - Hack around bugs in gcc-4.8.1 template handling | 
 |    - Faster opcode lookup | 
 |  - Validator: | 
 |    - Recognize extensions listed on SPIR-V registry, | 
 |      through #25 SPV_AMD_shader_fragment_mask | 
 |    - Validator issues an info message when it sees an unrecognized extension. | 
 |    - Type check basic arithmetic operations | 
 |    - Type check carry/extended arithmetic operations | 
 |    - Type check vector arithmetic operations | 
 |    - Type check Relational and Logical instructions | 
 |    - Type check Bit instructions | 
 |    - Check type uniqueness rules | 
 |    - Check conversion instructions | 
 |    - Check image instructions | 
 |    - Check derivative instructions | 
 |    - Check OpVectorShuffle | 
 |    - Check OpBranchConditional | 
 |    - OpModuleProcessed is only allowed after debug names section and before annotations | 
 |      section. | 
 |    - Checks the right kind of return is called for each function (void or non-void). | 
 |    - Add option to relax type check when storing structs (--relax-store-struct) | 
 |  - Optimizer: | 
 |    - Refactoring internal representation of the module, including: | 
 |      - IRContext: owns a module and manages analyses | 
 |      - Instructions are owned by intrusive lists, and have unique IDs | 
 |      - BasicBlock owns its instruction list. | 
 |      - DefUseManager: change representation of uses, for faster processing | 
 |        on large modules. | 
 |    - Add high level recipes: -O, -Os, and -Oconfig | 
 |      Recipes for -O and -Os are under development. | 
 |    - Add eliminate-dead-function transform | 
 |    - Add strength reduction transform: For now, convert multiply by power of 2 | 
 |      to a bit shift. | 
 |    - Add CFG cleanup transform | 
 |    - Add removal of dead module-scope variables | 
 |    - Add merge-return transform for modules without structured control flow | 
 |    - Add redundancy elimination within a basic block (local value numbering) | 
 |    - Extract-insert elimination: | 
 |      - Recognize the case where the first instruction in the sequence is an | 
 |        OpCompositeConstruct or OpConstantComposite | 
 |      - Handle some cases of nested structs | 
 |    - Dead branch elimination now can eliminate entire selection constructs | 
 |      when all arms are dead. | 
 |  - Compressing codec: | 
 |    - Updated algorithm to 1.01, 1.02, 1.03 | 
 |    - Not built by default.  Use -DSPIRV_BUILD_COMPRESSION=ON to build. | 
 |    - Codec can be parameterized by a customized model. | 
 |  - Fixes: | 
 |    #728: Fix decoration of inlined functions | 
 |    #798: spirv-as should fail when given unrecognized long option | 
 |    #800: Inliner: Fix inlining function into header of multi-block loop | 
 |    #824: Eliminate-local-multi-store: Fix a crash | 
 |    #826: Elimiante-local-multi-store: Fix a crash | 
 |    #827: Fix crash when compact-ids transform runs before another transform. | 
 |    #834: Add Cmake option to build the compressing codec. Off by default. | 
 |    #911: Fix classification of Line and NoLine instructions | 
 |  | 
 | v2017.0 2017-09-01 | 
 |  - Update README to describe that assembler, disassembler, and binary parser support | 
 |    are based on grammar files from the SPIRV-Headers repository. | 
 |  | 
 | v2016.7 2017-09-01 | 
 |  - Add SPIR-V 1.2 | 
 |  - OpenCL 2.2 support is now based on SPIR-V 1.2 | 
 |  - Support AMD extensions in assembler, disassembler: | 
 |     SPV_AMD_gcn_shader | 
 |     SPV_AMD_shader_ballot | 
 |     SPV_AMD_shader_explicit_vertex_parameter | 
 |     SPV_AMD_shader_trinary_minmax | 
 |     SPV_AMD_gpu_shader_half_float | 
 |     SPV_AMD_texture_gather_bias_lod | 
 |     SPV_AMD_gpu_shader_int16 | 
 |  - Optimizer: Add support for: | 
 |    - Inline all function calls in entry points. | 
 |    - Flatten decoration groups.  Fixes #602 | 
 |    - Id compaction (minimize Id bound).  Fixes #624 | 
 |    - Eliminate redundant composite insert followed by extract | 
 |    - Simplify access chains to local variables | 
 |    - Eliminate local variables with a single store, if possible | 
 |    - Eliminate local variables with a several stores, if possible | 
 |    - Eliminate loads and stores in same block to local variables | 
 |    - Eliminate redundant insert/extract to composite values | 
 |    - Aggressive dead instruction elimination | 
 |    - Eliminate dead branches | 
 |    - Merge blocks when the second can only be preceded by the first | 
 |    - Eliminate ommon uniform loads | 
 |  - Assembler: Add option to preserve numeric ids. Fixes #625 | 
 |  - Add build target spirv-tools-vimsyntax to generate spvasm.vim, a SPIR-V | 
 |    assembly syntax file for Vim. | 
 |  - Version string: Allow overriding of wall clock timestamp with contents | 
 |    of environment variable SOURCE_DATE_EPOCH. | 
 |  - Validator implements relaxed rules for SPV_KHR_16bit_storage. | 
 |  - CMake installation rules use GNUInstallDirs.  For example, libraries | 
 |    will be installed into a lib64 directory if that's the norm for the | 
 |    current system. | 
 |  - Fixes: | 
 |    #500: Parameterize validator limit checks | 
 |    #508: Support compilation under CYGWIN | 
 |    #517: Fix validation when continue (or case) contstruct is also the head of a | 
 |      nested control construct. | 
 |    #551: If a merge block is reachable, it must be *strictly* dominated by its | 
 |      header. | 
 |    #548: Validator: Error when the reserved OpImageSparseSampleProj* opcodes | 
 |      are used. | 
 |    #611: spvtools::Optimizer was failing to save the module to the output | 
 |      binary vector when all passes succeded without changes. | 
 |    #629: The inline-entry-points-all optimization could generate invalidly | 
 |      structured code when the inlined function had early returns. | 
 |    #697: Optimizer's Instruction::ForEachInId method was skipping semantics-id | 
 |      and scope-id. | 
 |    #755: Inliner: Fix inlining of callee with single Return appearing before | 
 |      the end of the function. | 
 |    #776: Fix dead branch elimination in presence of complex but dead control | 
 |      flow. | 
 |    #781: SPV_KHR_variable_pointers allows duplicate pointer types | 
 |    #782: Inliner: Fix remapping of non-label forward references in callee | 
 |    #787: Inliner: Fix remapping of inlined entry block when called from | 
 |      single block loop. | 
 |    #790: Inliner: Fix remapping of inlined entry block when callee has | 
 |      multiple returns. | 
 |  | 
 | v2016.6 2016-12-13 | 
 |  - Published the C++ interface for assembling, disassembling, validation, and | 
 |    optimization. | 
 |  - Support SPV_KHR_shader_draw_parameters in assembler, disassembler, parser. | 
 |  - Validator: | 
 |    - Add validator API accepting raw binary words | 
 |    - Increased coverage: | 
 |      - Checks "Data rules" in Universal Validation Rules, section 2.16.1 | 
 |      - WIP: Universal Limits. | 
 |        - The minimum mandated upper bounds are checked. | 
 |        - TODO: Parameterize the validator to allow larger limits accepted by | 
 |          a more than minimally capable implementation. | 
 |    - OpSampledImage checks | 
 |    - OpConstantComposite checks | 
 |    - Id bound check | 
 |  - Disasssembler: | 
 |    - Generates friendly GLSL-based names for more builtin variables | 
 |    - Generates friendly names for numeric OpConstant values | 
 |    - Vendor tool info extracted from SPIR-V XML registry file. | 
 |  - Fixes issues: | 
 |    #429: Validator: Allow OpTypeForwardPointer and OpTypeStruct to reference | 
 |      undefined IDs | 
 |    #482: Validator: OpVariable initializer can be an ID of a module-scope variable | 
 |  | 
 | v2016.5 2016-09-16 | 
 |  - Support SPV_KHR_shader_ballot in assembler, disassembler, parser. | 
 |  - Disassembler: Generate friendly names for built-in variables. | 
 |  - Partial fixes: | 
 |    #359: Add Emacs helper for automatically diassembling/assembling a SPIR-V | 
 |      binary on file load/save. | 
 |  - Fixes: | 
 |    #414: Validator: Allow OpUndef for composite constants | 
 |    #415: Validator: Phi can use its own value in some cases. | 
 |  | 
 | v2016.4 2016-09-01 | 
 |  - Relicensed under Apache 2.0 | 
 |  - Add optimization passes (in API and spirv-opt command) | 
 |    - Fold spec constants defined with OpSpecConstantOp and | 
 |        OpSpecConstantComposite to normal constants with fixed value(s). | 
 |  - Fixes issues: | 
 |    #318: Relicensed under Apache 2.0 | 
 |  | 
 | v2016.3 2016-08-24 | 
 |  - Add target environment enums for OpenCL 2.1, OpenCL 2.2, | 
 |    OpenGL 4.0, OpenGL 4.1, OpenGL 4.2, OpenGL 4.3, OpenGL 4.5. | 
 |  - Add spirv-cfg, an experimental tool to dump the control flow graph | 
 |    as a GraphiViz "dot" graph | 
 |  - Add optimization pass: Eliminate dead constants. | 
 |  - Add spirv-lesspipe.sh filter utility | 
 |  - Fixes issues: | 
 |    #288: Check def-use dominance rules for OpPhi (variable,parent) operands | 
 |    #339: Allow OpUndef in types-constants-global-vars section, as required | 
 |      by SPIR-V 1.0 Rev7, 1.1 Rev 3. | 
 |    #340: Avoid race on mkdir during build | 
 |    #365: Relax PointSize, ClipDistance, CullDistance capability check in all | 
 |      environments not just Vulkan 1.0. | 
 |  | 
 | v2016.2 2016-08-05 | 
 |  - Validator is incomplete | 
 |    - Checks ID use block is dominated by definition block | 
 |  - Add optimization passes (in API and spirv-opt command) | 
 |    - Strip debug info instructions | 
 |    - Freeze spec constant to their default values | 
 |  - Allow INotEqual as operation for OpSpecConstantOp | 
 |  - Fixes bugs: | 
 |    #270: validator: crash when continue construct is unreachable | 
 |    #279: validator: infinite loop when analyzing some degenerate control | 
 |      flow graphs | 
 |    #286: validator: don't incorrectly generate def-use error for | 
 |          (variable,parent) parameters to OpPhi | 
 |    #290: disassembler: never generate bare % for an identifier | 
 |    #295: validator: def-use dominance check should ignore unreachable uses | 
 |    #276: validator: allow unreachable continue constructs | 
 |    #297: validator: allow an unreachable block to branch to a reachable | 
 |          merge block | 
 |  | 
 | v2016.1 2016-07-19 | 
 |  - Fix https://github.com/KhronosGroup/SPIRV-Tools/issues/261 | 
 |    Turn off ClipDistance and CullDistance capability checks for Vulkan. | 
 |  - The disassembler can emit friendly names based on debug info (OpName | 
 |    instructions), and will infer somewhat friendly names for most types. | 
 |    This is turned on by default for the spirv-dis command line tool. | 
 |  - Updated to support SPIR-V 1.1 rev 2 | 
 |    - Input StorageClass, Sampled1D capability, and SampledBuffer capability | 
 |      do not require Shader capability anymore. | 
 |  | 
 | v2016.0 2016-07-04 | 
 |  | 
 |  - Adds v<year>.<index> versioning, with "-dev" indicating | 
 |    work in progress.  The intent is to more easly report | 
 |    and summarize functionality when SPIRV-Tools is incorporated | 
 |    in downstream projects. | 
 |  | 
 |  - Summary of functionality (See the README.md for more): | 
 |    - Supports SPIR-V 1.1 Rev 1 | 
 |    - Supports SPIR-V 1.0 Rev 5 | 
 |    - Supports GLSL std450 extended instructions 1.0 Rev 3 | 
 |    - Supports OpenCL extended instructions 1.0 Rev 2 | 
 |    - Assembler, disassembler are complete | 
 |      - Supports floating point widths of 16, 32, 64 bits | 
 |      - Supports integer widths up to 64 bits | 
 |    - Validator is incomplete | 
 |      - Checks capability requirements in most cases | 
 |      - Checks module layout constraints | 
 |      - Checks ID use-definition ordering constraints, | 
 |        ignoring control flow | 
 |      - Checks some control flow graph rules | 
 |    - Optimizer is introduced, with few available transforms. | 
 |    - Supported on Linux, OSX, Android, Windows | 
 |  | 
 |  - Fixes bugs: | 
 |    - #143: OpenCL pow and pown arguments |