Support 16-byte aligned stack on 32-bit Windows.
On Windows x86-32, the ABI only guarantees the stack to be 4-byte
aligned. We therefore need the stack pointer to be explicitly
aligned when using vectors. This demands using a frame pointer (to
access function arguments). Also, we had to change accessing spilled
variables from the stack pointer instead of the frame pointer so they
are also aligned. This change does not affect PNaCl. Projects using
the Microsoft ABI should define SUBZERO_USE_MICROSOFT_ABI.
BUG=swiftshader:29
Change-Id: I186ce9435244d6fa9494ec514a91122b6be130b3
Reviewed-on: https://chromium-review.googlesource.com/427348
Reviewed-by: Jim Stichnoth <stichnot@chromium.org>
diff --git a/src/IceTargetLowering.h b/src/IceTargetLowering.h
index 41108f8..bfe0a0e 100644
--- a/src/IceTargetLowering.h
+++ b/src/IceTargetLowering.h
@@ -250,6 +250,7 @@
virtual RegNumT getFrameOrStackReg() const = 0;
virtual size_t typeWidthInBytesOnStack(Type Ty) const = 0;
virtual uint32_t getStackAlignment() const = 0;
+ virtual bool needsStackPointerAlignment() const { return false; }
virtual void reserveFixedAllocaArea(size_t Size, size_t Align) = 0;
virtual int32_t getFrameFixedAllocaOffset() const = 0;
virtual uint32_t maxOutArgsSizeBytes() const { return 0; }