[llvm] AMDGPU: Set transient stack alignment to 4 (PR #193517)

[Jay Foad via llvm-commits]

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@@ -185,7 +185,8 @@ GCNSubtarget::GCNSubtarget(const Triple &TT, StringRef GPU, StringRef FS,
     InstrItins(getInstrItineraryForCPU(GPU)),
     InstrInfo(initializeSubtargetDependencies(TT, GPU, FS)),
     TLInfo(TM, *this),
-    FrameLowering(TargetFrameLowering::StackGrowsUp, getStackAlignment(), 0) {
+    FrameLowering(TargetFrameLowering::StackGrowsUp, getStackAlignment(), 0,
+                  /*TransAl=*/Align(4)) {
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jayfoad wrote:

Add a comment to say why it's needed?

https://github.com/llvm/llvm-project/pull/193517