Support initializers on global variables in SkSL to SkVM
Bug: skia:11295
Change-Id: I72c09b75a3ff5d668e99dcc3620850b82071b560
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/371340
Reviewed-by: Mike Klein <mtklein@google.com>
diff --git a/src/sksl/SkSLVMGenerator.cpp b/src/sksl/SkSLVMGenerator.cpp
index c7bb702..d17d1a2 100644
--- a/src/sksl/SkSLVMGenerator.cpp
+++ b/src/sksl/SkSLVMGenerator.cpp
@@ -424,8 +424,9 @@
size_t fpCount = 0;
for (const ProgramElement* e : fProgram.elements()) {
if (e->is<GlobalVarDeclaration>()) {
- const GlobalVarDeclaration& decl = e->as<GlobalVarDeclaration>();
- const Variable& var = decl.declaration()->as<VarDeclaration>().var();
+ const GlobalVarDeclaration& gvd = e->as<GlobalVarDeclaration>();
+ const VarDeclaration& decl = gvd.declaration()->as<VarDeclaration>();
+ const Variable& var = decl.var();
SkASSERT(fVariableMap.find(&var) == fVariableMap.end());
// For most variables, fVariableMap stores an index into fSlots, but for fragment
@@ -439,8 +440,10 @@
// special types like 'void'. Of those, only fragment processors are legal variables.
SkASSERT(!var.type().isOpaque());
- size_t nslots = slot_count(var.type());
- fVariableMap[&var] = fSlots.size();
+ // getSlot() allocates space for the variable's value in fSlots, initializes it to zero,
+ // and populates fVariableMap.
+ size_t slot = this->getSlot(var),
+ nslots = slot_count(var.type());
if (int builtin = var.modifiers().fLayout.fBuiltin; builtin >= 0) {
// builtin variables are system-defined, with special semantics. The only builtin
@@ -448,10 +451,10 @@
switch (builtin) {
case SK_FRAGCOORD_BUILTIN:
SkASSERT(nslots == 4);
- fSlots.insert(fSlots.end(), {device.x.id,
- device.y.id,
- fBuilder->splat(0.0f).id,
- fBuilder->splat(1.0f).id});
+ fSlots[slot + 0] = device.x.id;
+ fSlots[slot + 1] = device.y.id;
+ fSlots[slot + 2] = fBuilder->splat(0.0f).id;
+ fSlots[slot + 3] = fBuilder->splat(1.0f).id;
break;
default:
SkDEBUGFAIL("Unsupported builtin");
@@ -459,11 +462,14 @@
} else if (is_uniform(var)) {
// For uniforms, copy the supplied IDs over
SkASSERT(uniformIter + nslots <= uniforms.end());
- fSlots.insert(fSlots.end(), uniformIter, uniformIter + nslots);
+ std::copy(uniformIter, uniformIter + nslots, fSlots.begin() + slot);
uniformIter += nslots;
- } else {
- // For other globals, initialize them to zero
- fSlots.insert(fSlots.end(), nslots, fBuilder->splat(0.0f).id);
+ } else if (decl.value()) {
+ // For other globals, populate with the initializer expression (if there is one)
+ Value val = this->writeExpression(*decl.value());
+ for (size_t i = 0; i < nslots; ++i) {
+ fSlots[slot + i] = val[i];
+ }
}
}
}
@@ -517,8 +523,6 @@
return entry->second;
}
- SkASSERT(!is_uniform(v)); // Should have been added at construction time
-
size_t slot = fSlots.size(),
nslots = slot_count(v.type());
fSlots.resize(slot + nslots, fBuilder->splat(0.0f).id);
diff --git a/tests/sksl/runtime/GlobalVariables.skvm b/tests/sksl/runtime/GlobalVariables.skvm
index e022147..6cdeab8 100644
--- a/tests/sksl/runtime/GlobalVariables.skvm
+++ b/tests/sksl/runtime/GlobalVariables.skvm
@@ -1,8 +1,8 @@
2 registers, 6 instructions:
0 r0 = splat 0 (0)
-1 r1 = splat 40000000 (2)
+1 r1 = splat 3F800000 (1)
loop:
2 store32 ptr1 r0
-3 store32 ptr2 r0
+3 store32 ptr2 r1
4 store32 ptr3 r0
5 store32 ptr4 r1
