InstCombine: Check GEP operand is available #160438
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Logic copied from the select case. Fixes #160302
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@llvm/pr-subscribers-llvm-transforms @llvm/pr-subscribers-backend-amdgpu Author: Matt Arsenault (arsenm) ChangesLogic copied from the select case. Fixes #160302 Full diff: https://github.com/llvm/llvm-project/pull/160438.diff 2 Files Affected:
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index 53e77e6cc5c31..9491610190c10 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -338,8 +338,18 @@ bool PointerReplacer::collectUsers() {
if (!TryPushInstOperand(TrueInst) || !TryPushInstOperand(FalseInst))
return false;
} else if (auto *GEP = dyn_cast<GetElementPtrInst>(Inst)) {
- UsersToReplace.insert(GEP);
- PushUsersToWorklist(GEP);
+ auto *PtrOp = dyn_cast<Instruction>(GEP->getPointerOperand());
+ if (!PtrOp)
+ return false;
+ if (isAvailable(PtrOp)) {
+ UsersToReplace.insert(GEP);
+ PushUsersToWorklist(GEP);
+ continue;
+ }
+
+ Worklist.emplace_back(GEP);
+ if (!TryPushInstOperand(PtrOp))
+ return false;
} else if (auto *MI = dyn_cast<MemTransferInst>(Inst)) {
if (MI->isVolatile())
return false;
diff --git a/llvm/test/Transforms/InstCombine/AMDGPU/ptr-replace-alloca.ll b/llvm/test/Transforms/InstCombine/AMDGPU/ptr-replace-alloca.ll
index beb84362b7f92..90877be255e0f 100644
--- a/llvm/test/Transforms/InstCombine/AMDGPU/ptr-replace-alloca.ll
+++ b/llvm/test/Transforms/InstCombine/AMDGPU/ptr-replace-alloca.ll
@@ -109,4 +109,23 @@ bb:
ret void
}
+@global = external addrspace(1) constant [16 x float], align 64
+
+define float @issue160302(i1 %cond, ptr addrspace(5) %arg) {
+; CHECK-LABEL: define float @issue160302(
+; CHECK-SAME: i1 [[COND:%.*]], ptr addrspace(5) [[ARG:%.*]]) {
+; CHECK-NEXT: [[AGG_TMP2_I4:%.*]] = alloca [16 x float], align 64, addrspace(5)
+; CHECK-NEXT: [[SELECT_PTR:%.*]] = select i1 [[COND]], ptr addrspace(5) [[AGG_TMP2_I4]], ptr addrspace(5) [[ARG]]
+; CHECK-NEXT: [[COND_I:%.*]] = load float, ptr addrspace(5) [[SELECT_PTR]], align 4
+; CHECK-NEXT: ret float [[COND_I]]
+;
+ %agg.tmp2.i4 = alloca [16 x float], align 64, addrspace(5)
+ call void @llvm.memcpy.p5.p1.i64(ptr addrspace(5) %agg.tmp2.i4, ptr addrspace(1) @global, i64 0, i1 false)
+ %m_Data.i14.i = getelementptr [16 x float], ptr addrspace(5) %agg.tmp2.i4, i32 0, i32 0
+ %gep = getelementptr [16 x float], ptr addrspace(5) %arg, i32 0, i32 0
+ %select.ptr = select i1 %cond, ptr addrspace(5) %m_Data.i14.i, ptr addrspace(5) %gep
+ %cond.i = load float, ptr addrspace(5) %select.ptr, align 4
+ ret float %cond.i
+}
+
declare void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) noalias writeonly captures(none), ptr addrspace(4) noalias readonly captures(none), i64, i1 immarg) #0
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gandhi56
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Sep 24, 2025
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LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/51/builds/24113 Here is the relevant piece of the build log for the reference |
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Oct 3, 2025
Logic copied from the select case. Fixes llvm#160302
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Logic copied from the select case.
Fixes #160302