[llvm] [indvars] Missing variables at Og: (PR #69920)

[Felipe de Azevedo Piovezan via llvm-commits]

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@@ -0,0 +1,87 @@
+; RUN: opt -passes=indvars -S -o - < %s | FileCheck %s
+
+; Missing local variable 'Index' after loop 'Induction Variable Elimination'.
+; When adding a breakpoint at line 11, LLDB does not have information on
+; the variable. But it has info on 'Var' and 'End'.
+
+;  1	__attribute__((optnone)) int nop(int Param) {
+;  2	  return 0;
+;  3	}
+;  4
+;  5	void bar() {
+;  6    int End = 777;
+;  7	  int Index = 27;
+;  8	  char Var = 1;
+;  9	  for (; Index < End; ++Index)
+; 10	    ;
+; 11	  nop(Index);
+; 12	}
+; 13
+; 14	int main () {
+; 15	  bar();
+; 16	}
+
+; CHECK: for.cond: {{.*}}
+; CHECK:   call void @llvm.dbg.value(metadata i32 %Index.{{[0-9]+}}, metadata ![[DBG:[0-9]+]], {{.*}}
+; CHECK:   call void @llvm.dbg.value(metadata i32 %inc, metadata ![[DBG:[0-9]+]], {{.*}}
+; CHECK: for.end: {{.*}}
+; CHECK:   call void @llvm.dbg.value(metadata i32 777, metadata ![[DBG:[0-9]+]], {{.*}}
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felipepiovezan wrote:

if I understand this test correctly, all of these dbg.values are for the variable `Index`, right? I think it's important that we label the first occurrence of it and check that all three of these intrinsics are referring to it (right now we allow any metadata there)

https://github.com/llvm/llvm-project/pull/69920