Salvage debug info from ptrauth intrinsics.

rdar://80227769

Author: adrian-prantl

llvm/lib/Transforms/Coroutines/CoroFrame.cpp

@@ -2527,11 +2527,6 @@ void coro::salvageDebugInfo(
         Expr = DIExpression::prepend(Expr, DIExpression::DerefBefore);
     } else if (auto *StInst = dyn_cast<StoreInst>(Inst)) {
       Storage = StInst->getOperand(0);
-    } else if (auto *IInst = dyn_cast<llvm::IntrinsicInst>(Inst)) {
-      if (IInst->getIntrinsicID() == Intrinsic::ptrauth_auth)
-        Storage = IInst->getArgOperand(0);
-      else
-        break;
     } else if (auto *Phi = dyn_cast<PHINode>(Inst)) {
       if (Phi->getNumIncomingValues() != 1)
         return;

llvm/lib/Transforms/Utils/Local.cpp

@@ -1937,6 +1937,11 @@ Value *llvm::salvageDebugInfoImpl(Instruction &I, uint64_t CurrentLocOps,
   // *Not* to do: we should not attempt to salvage load instructions,
   // because the validity and lifetime of a dbg.value containing
   // DW_OP_deref becomes difficult to analyze. See PR40628 for examples.
+
+  if (auto *IInst = dyn_cast<llvm::IntrinsicInst>(&I))
+    if (IInst->getIntrinsicID() == Intrinsic::ptrauth_auth)
+      return IInst->getArgOperand(0);
+
   return nullptr;
 }
 

llvm/test/DebugInfo/AArch64/salvage-ptrauth.ll

@@ -0,0 +1,27 @@
+; RUN: opt -mtriple arm64e-apple-darwin -adce %s -S -o - | FileCheck %s
+target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
+
+declare i64 @llvm.ptrauth.auth.i64(i64, i32, i64)
+
+define void @f(i64 %arg, i64 %arg1) !dbg !8 {
+entry:
+  %tmp = call i64 @llvm.ptrauth.auth.i64(i64 %arg, i32 0, i64 %arg1)
+  ; CHECK: call void @llvm.dbg.value(metadata i64 %arg,
+  ; CHECK-SAME: !DIExpression())
+  call void @llvm.dbg.value(metadata i64 %tmp, metadata !11, metadata !DIExpression()), !dbg !13
+  ret void, !dbg !13
+}
+declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, emissionKind: FullDebug)
+!1 = !DIFile(filename: "salavage.c", directory: "/")
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!8 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !9, isLocal: false, isDefinition: true, scopeLine: 1, isOptimized: false, unit: !0)
+!9 = !DISubroutineType(types: !10)
+!10 = !{null}
+!11 = !DILocalVariable(name: "x", scope: !8, file: !1, line: 2, type: !12)
+!12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!13 = !DILocation(line: 1, column: 1, scope: !8)