[llvm] [GVN] Skip debug instructions in findDominatingValue function (PR #65977)

[Sergey Kachkov via llvm-commits]

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@@ -0,0 +1,46 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt < %s -passes=gvn -gvn-max-num-visited-insts=4 -S | FileCheck %s
+
+declare void @llvm.dbg.declare(metadata, metadata, metadata)
+
+define i32 @foo(ptr %a, ptr %b) {
+; CHECK-LABEL: define i32 @foo(
+; CHECK-SAME: ptr [[A:%.*]], ptr [[B:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP0:%.*]] = load i32, ptr [[A]], align 4
+; CHECK-NEXT:    call void @llvm.dbg.declare(metadata ptr undef, metadata [[META4:![0-9]+]], metadata !DIExpression()), !dbg [[DBG14:![0-9]+]]
+; CHECK-NEXT:    [[TMP1:%.*]] = load i32, ptr [[B]], align 4
+; CHECK-NEXT:    [[COND:%.*]] = icmp slt i32 [[TMP0]], [[TMP1]]
+; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[COND]], i32 [[TMP0]], i32 [[TMP1]]
+; CHECK-NEXT:    [[PTR:%.*]] = select i1 [[COND]], ptr [[A]], ptr [[B]]
+; CHECK-NEXT:    ret i32 [[TMP2]]
+;
+entry:
+  %0 = load i32, ptr %a, align 4
+  call void @llvm.dbg.declare(metadata ptr undef, metadata !46, metadata !DIExpression()), !dbg !40
+  %1 = load i32, ptr %b, align 4
+  %cond = icmp slt i32 %0, %1
+  %ptr = select i1 %cond, ptr %a, ptr %b
+  %res = load i32, ptr %ptr, align 4
+  ret i32 %res
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!35, !36}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C11, file: !1, producer: "clang version 17.0.0.prerel", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: "bbi-78272.c", directory: "/tmp")
+!5 = !DIBasicType(name: "int", size: 16, encoding: DW_ATE_signed)
+
+!35 = !{i32 7, !"Dwarf Version", i32 4}
+!36 = !{i32 2, !"Debug Info Version", i32 3}
+!40 = !DILocation(line: 15, column: 7, scope: !41)
+!41 = distinct !DISubprogram(name: "x", scope: !1, file: !1, line: 14, type: !42, scopeLine: 14, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !45)
+!42 = !DISubroutineType(types: !43)
+!43 = !{!5}
+!45 = !{!46, !47, !48, !49, !50}
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skachkov-sc wrote:

Done

https://github.com/llvm/llvm-project/pull/65977