Merge pull request #1273 from billhollings/simulator-buffer-alignment
Set Metal buffer alignment to 256 on non-Apple Silicon iOS/tvOS simulators.
diff --git a/Common/MVKCommonEnvironment.h b/Common/MVKCommonEnvironment.h
index 6d72a85..2e61f97 100644
--- a/Common/MVKCommonEnvironment.h
+++ b/Common/MVKCommonEnvironment.h
@@ -77,19 +77,19 @@
# define MVK_OS_SIMULATOR TARGET_OS_SIMULATOR
#endif
-/** Building for macOS with support for Apple Silicon. */
-#ifndef MVK_MACOS_APPLE_SILICON
-# define MVK_MACOS_APPLE_SILICON (__MAC_OS_X_VERSION_MAX_ALLOWED >= 101600)
+/** Building for Apple Silicon on iOS, tvOS, or macOS platform. */
+#ifndef MVK_APPLE_SILICON
+# define MVK_APPLE_SILICON TARGET_CPU_ARM64
#endif
-/** Building for Apple Silicon. */
-#ifndef MVK_APPLE_SILICON
-# define MVK_APPLE_SILICON (MVK_IOS || MVK_TVOS || MVK_MACOS_APPLE_SILICON)
+/** Building for macOS with support for Apple Silicon. */
+#ifndef MVK_MACOS_APPLE_SILICON
+# define MVK_MACOS_APPLE_SILICON (MVK_MACOS && MVK_APPLE_SILICON)
#endif
/** Building with Xcode 12. */
#ifndef MVK_XCODE_12
-# define MVK_XCODE_12 (MVK_MACOS_APPLE_SILICON || \
+# define MVK_XCODE_12 ((__MAC_OS_X_VERSION_MAX_ALLOWED >= 101600) || \
(__IPHONE_OS_VERSION_MAX_ALLOWED >= 140000)) // Also covers tvOS
#endif
diff --git a/MoltenVK/MoltenVK/GPUObjects/MVKDevice.mm b/MoltenVK/MoltenVK/GPUObjects/MVKDevice.mm
index 8d60d71..b39af4c 100644
--- a/MoltenVK/MoltenVK/GPUObjects/MVKDevice.mm
+++ b/MoltenVK/MoltenVK/GPUObjects/MVKDevice.mm
@@ -1428,7 +1428,7 @@
if (supportsMTLGPUFamily(Apple5)) {
// This is an Apple GPU--treat it accordingly.
_metalFeatures.mtlCopyBufferAlignment = 1;
- _metalFeatures.mtlBufferAlignment = 16;
+ _metalFeatures.mtlBufferAlignment = 16; // Min float4 alignment for typical vertex buffers. MTLBuffer may go down to 4 bytes for other data.
_metalFeatures.maxQueryBufferSize = (64 * KIBI);
_metalFeatures.maxPerStageDynamicMTLBufferCount = _metalFeatures.maxPerStageBufferCount;
_metalFeatures.postDepthCoverage = true;
@@ -1545,6 +1545,11 @@
break;
#endif
}
+
+// iOS and tvOS adjustments necessary when running in the simulator on non-Apple GPUs.
+#if MVK_OS_SIMULATOR && !MVK_APPLE_SILICON
+ _metalFeatures.mtlBufferAlignment = 256;
+#endif
}
// Initializes the physical device features of this instance.
