[llvm] [DAGCombiner] Preserve debug location of original load in fold (conv (load x)) (PR #160236)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,41 @@
+; RUN: llc -mtriple=amdgcn -mcpu=gfx942  < %s | FileCheck %s
+
+; CHECK-LABEL:  test:
+; CHECK:        .loc    1 8 16                          ; test.py:8:16
+; CHECK-NEXT:   s_load_dword
+
+; Function Attrs: alwaysinline mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: readwrite)
+define amdgpu_kernel void @test(ptr addrspace(1) inreg readonly captures(none) %0, ptr addrspace(1) inreg writeonly captures(none) %1, ptr addrspace(1) inreg readnone captures(none) %2, ptr addrspace(1) inreg readnone captures(none) %3) local_unnamed_addr #0 !dbg !4 {
+  %5 = tail call i32 @llvm.amdgcn.workitem.id.x(), !dbg !7
+  %6 = and i32 %5, 255, !dbg !7
+  %7 = icmp eq i32 %6, 0, !dbg !7
+  br i1 %7, label %8, label %10, !dbg !7
+
+8:                                                ; preds = %4
+  %9 = load <1 x float>, ptr addrspace(1) %0, align 4, !dbg !8, !amdgpu.noclobber !6
+  store <1 x float> %9, ptr addrspace(1) %1, align 4, !dbg !7
+  br label %10, !dbg !7
+
+10:                                               ; preds = %8, %4
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arsenm wrote:

Shouldn't need multiple blocks? 

https://github.com/llvm/llvm-project/pull/160236