[llvm] [InstCombine] Fix a crash in `PointerReplacer` (PR #98987)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,33 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -passes=instcombine -S -o - %s | FileCheck %s
+; REQUIRES: amdgpu-registered-target
+
+target triple = "amdgcn-amd-amdhsa"
+
+%anon = type { i32, [8 x ptr], ptr }
+
+define amdgpu_kernel void @foo(ptr addrspace(4) byref(%anon) align 8 %0) {
+; CHECK-LABEL: @foo(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP1:%.*]] = load ptr, ptr addrspace(4) [[TMP0:%.*]], align 8
+; CHECK-NEXT:    br label [[FOR_COND10:%.*]]
+; CHECK:       for.cond10:
+; CHECK-NEXT:    [[TMP2:%.*]] = load i64, ptr [[TMP1]], align 8
+; CHECK-NEXT:    store i64 [[TMP2]], ptr addrspace(1) null, align 8
+; CHECK-NEXT:    br label [[FOR_COND10]]
+;
+entry:
+  %coerce = alloca %anon, addrspace(5)
+  call void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) %coerce, ptr addrspace(4) %0, i64 0, i1 false)
+  %1 = addrspacecast ptr addrspace(5) %coerce to ptr
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arsenm wrote:

Use named values in tests 

https://github.com/llvm/llvm-project/pull/98987