[llvm] [Dwarf][Transforms] Add dwarf support when func signature changed (PR #127855)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,103 @@
+; REQUIRES: x86-registered-target
+; RUN: opt -O2 -S < %s | FileCheck %s
+;
+; Source code:
+;   int tar(int a);
+;   __attribute__((noinline)) static int foo(int a, int b)
+;   {
+;     return tar(a) + tar(a + 1);
+;   }
+;   int bar(int a)
+;   {
+;     foo(a, 1);
+;     return 0;
+;   }
+; Compilation flag:
+;   clang -O2 -g -S -emit-llvm -Xclang -disable-llvm-passes test.c
+
+; ModuleID = 'test.c'
+source_filename = "test.c"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function Attrs: nounwind uwtable
+define dso_local i32 @bar(i32 noundef %0) #0 !dbg !9 {
+  %2 = alloca i32, align 4
+  store i32 %0, ptr %2, align 4, !tbaa !15
+    #dbg_declare(ptr %2, !14, !DIExpression(), !19)
+  %3 = load i32, ptr %2, align 4, !dbg !20, !tbaa !15
+  %4 = call i32 @foo(i32 noundef %3, i32 noundef 1), !dbg !21
+  ret i32 0, !dbg !22
+}
+
+; Function Attrs: noinline nounwind uwtable
+define internal i32 @foo(i32 noundef %0, i32 noundef %1) #1 !dbg !23 {
+  %3 = alloca i32, align 4
+  %4 = alloca i32, align 4
+  store i32 %0, ptr %3, align 4, !tbaa !15
+    #dbg_declare(ptr %3, !27, !DIExpression(), !29)
+  store i32 %1, ptr %4, align 4, !tbaa !15
+    #dbg_declare(ptr %4, !28, !DIExpression(), !30)
+  %5 = load i32, ptr %3, align 4, !dbg !31, !tbaa !15
+  %6 = call i32 @tar(i32 noundef %5), !dbg !32
+  %7 = load i32, ptr %3, align 4, !dbg !33, !tbaa !15
+  %8 = add nsw i32 %7, 1, !dbg !34
+  %9 = call i32 @tar(i32 noundef %8), !dbg !35
+  %10 = add nsw i32 %6, %9, !dbg !36
+  ret i32 %10, !dbg !37
+}
+
+; CHECK: define internal fastcc void @foo(i32 noundef %0)
+
+declare !dbg !38 i32 @tar(i32 noundef) #2
+
+attributes #0 = { nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+attributes #1 = { noinline nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+attributes #2 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
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arsenm wrote:

Remove unnecessary attributes 

https://github.com/llvm/llvm-project/pull/127855