[llvm] r254887 - [Verifier] Fix !dbg validation if Scope is the Subprogram

[Keno Fischer via llvm-commits]

Author: kfischer
Date: Sun Dec  6 17:05:38 2015
New Revision: 254887

URL: http://llvm.org/viewvc/llvm-project?rev=254887&view=rev
Log:
[Verifier] Fix !dbg validation if Scope is the Subprogram

Summary:
We are inserting both Scope and SP into the Seen map and check whether
it was already there in which case we skip the validation (the idea
being that we already checked this Subprogram before). However,
if (Scope == SP) as MDNodes, then inserting the Scope, will trigger
the Seen check causing us to incorrectly not validate this !dbg
attachment. Fix this by not performing the SP Seen check if Scope == SP

Reviewers: pcc, dexonsmith, dblaikie

Subscribers: dblaikie, llvm-commits

Differential Revision: http://reviews.llvm.org/D14697

Added:
    llvm/trunk/test/Verifier/func-dbg.ll
Modified:
    llvm/trunk/lib/IR/Verifier.cpp
    llvm/trunk/test/CodeGen/X86/2010-05-28-Crash.ll

Modified: llvm/trunk/lib/IR/Verifier.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/Verifier.cpp?rev=254887&r1=254886&r2=254887&view=diff
==============================================================================
--- llvm/trunk/lib/IR/Verifier.cpp (original)
+++ llvm/trunk/lib/IR/Verifier.cpp Sun Dec  6 17:05:38 2015
@@ -1814,7 +1814,10 @@ void Verifier::visitFunction(const Funct
         continue;
 
       DISubprogram *SP = Scope ? Scope->getSubprogram() : nullptr;
-      if (SP && !Seen.insert(SP).second)
+
+      // Scope and SP could be the same MDNode and we don't want to skip
+      // validation in that case
+      if (SP && ((Scope != SP) && !Seen.insert(SP).second))
         continue;
 
       // FIXME: Once N is canonical, check "SP == &N".

Modified: llvm/trunk/test/CodeGen/X86/2010-05-28-Crash.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/2010-05-28-Crash.ll?rev=254887&r1=254886&r2=254887&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/2010-05-28-Crash.ll (original)
+++ llvm/trunk/test/CodeGen/X86/2010-05-28-Crash.ll Sun Dec  6 17:05:38 2015
@@ -16,7 +16,7 @@ declare void @llvm.dbg.value(metadata, i
 define i32 @bar(i32 %x) nounwind optsize ssp !dbg !8 {
 entry:
   tail call void @llvm.dbg.value(metadata i32 %x, i64 0, metadata !7, metadata !DIExpression()), !dbg !DILocation(scope: !8)
-  tail call void @llvm.dbg.value(metadata i32 1, i64 0, metadata !0, metadata !DIExpression()) nounwind, !dbg !DILocation(scope: !1)
+  tail call void @llvm.dbg.value(metadata i32 1, i64 0, metadata !0, metadata !DIExpression()) nounwind, !dbg !DILocation(scope: !1, inlinedAt: !DILocation(scope: !8))
   %0 = tail call i32 (...) @zoo(i32 1) nounwind, !dbg !12 ; <i32> [#uses=1]
   %1 = add nsw i32 %0, %x, !dbg !13               ; <i32> [#uses=1]
   ret i32 %1, !dbg !13

Added: llvm/trunk/test/Verifier/func-dbg.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Verifier/func-dbg.ll?rev=254887&view=auto
==============================================================================
--- llvm/trunk/test/Verifier/func-dbg.ll (added)
+++ llvm/trunk/test/Verifier/func-dbg.ll Sun Dec  6 17:05:38 2015
@@ -0,0 +1,25 @@
+; RUN: not llvm-as < %s -o /dev/null 2>&1 | FileCheck %s
+
+define i32 @foo() !dbg !4 {
+entry:
+  ret i32 0, !dbg !6
+}
+
+define i32 @bar() !dbg !5 {
+entry:
+; CHECK: !dbg attachment points at wrong subprogram for function
+  ret i32 0, !dbg !6
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!7, !8}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang", isOptimized: false, runtimeVersion: 0, emissionKind: 0, enums: !2, retainedTypes: !2, subprograms: !3, globals: !2, imports: !2)
+!1 = !DIFile(filename: "dwarf-test.c", directory: "test")
+!2 = !{}
+!3 = !{!4, !5}
+!4 = distinct !DISubprogram(name: "foo", scope: !0, isDefinition: true)
+!5 = distinct !DISubprogram(name: "bar", scope: !0, isDefinition: true)
+!6 = !DILocation(line: 7, scope: !4)
+!7 = !{i32 2, !"Dwarf Version", i32 3}
+!8 = !{i32 1, !"Debug Info Version", i32 3}