[llvm] fc84323 - AMDGPU: Set transient stack alignment to 4 (#193517)

[via llvm-commits]

Author: Matt Arsenault
Date: 2026-04-23T11:01:54+01:00
New Revision: fc843236738b5b8085f393a22c421bee9d053233

URL: https://github.com/llvm/llvm-project/commit/fc843236738b5b8085f393a22c421bee9d053233
DIFF: https://github.com/llvm/llvm-project/commit/fc843236738b5b8085f393a22c421bee9d053233.diff

LOG: AMDGPU: Set transient stack alignment to 4 (#193517)

Added: 
    

Modified: 
    llvm/lib/Target/AMDGPU/GCNSubtarget.cpp

Removed: 
    


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diff  --git a/llvm/lib/Target/AMDGPU/GCNSubtarget.cpp b/llvm/lib/Target/AMDGPU/GCNSubtarget.cpp
index c56a746d63000..e6a13d5e0f115 100644
--- a/llvm/lib/Target/AMDGPU/GCNSubtarget.cpp
+++ b/llvm/lib/Target/AMDGPU/GCNSubtarget.cpp
@@ -185,7 +185,9 @@ 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) {
+    // Frame index expansion sometimes assumes the low bit of SP is 0
+    FrameLowering(TargetFrameLowering::StackGrowsUp, getStackAlignment(), 0,
+                  /*TransAl=*/Align(4)) {
   // clang-format on
   MaxWavesPerEU = AMDGPU::IsaInfo::getMaxWavesPerEU(this);
   EUsPerCU = AMDGPU::IsaInfo::getEUsPerCU(this);