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

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,157 @@
+; REQUIRES: x86-registered-target
+; RUN: opt -O3 -S < %s | FileCheck %s
+;
+; Source code:
+;   __attribute__((noinline)) static int is_absolute_path(const char *path)
+;   {
+;     return path[0] == '/';
+;   }
+;
+;   int scpy(char *, const char *, int);
+;   int quit(void);
+;   const char *make_nonrelative_path(char *buf, int sz, const char *path)
+;   {
+;     if (is_absolute_path(path)) {
+;       if (scpy(buf, path, sz) >= sz)
+;         quit();
+;     }
+;     return buf;
+;   }
+; 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 ptr @make_nonrelative_path(ptr noundef %0, i32 noundef %1, ptr noundef %2) #0 !dbg !9 {
+  %4 = alloca ptr, align 8
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arsenm wrote:

This function should be simplified to show a minimal example 

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