[llvm] 137597d - Add a verifier check that rejects non-distinct DISubprogram function

[Adrian Prantl via llvm-commits]

Author: Adrian Prantl
Date: 2020-09-25T12:04:46-07:00
New Revision: 137597d4f47854bb1701f6883d5c91e8a14d29a2

URL: https://github.com/llvm/llvm-project/commit/137597d4f47854bb1701f6883d5c91e8a14d29a2
DIFF: https://github.com/llvm/llvm-project/commit/137597d4f47854bb1701f6883d5c91e8a14d29a2.diff

LOG: Add a verifier check that rejects non-distinct DISubprogram function
attachments. They would crash the backend, which expects all
DISubprograms that are not part of the type system to have a unit field.

Clang right before https://reviews.llvm.org/D79967 would generate this
kind of broken IR.

rdar://problem/69534688

Thanks to Fangrui for fixing an assembler test I had missed!

https://reviews.llvm.org/D88270

Added: 
    llvm/test/Verifier/unique-disubprogram.ll

Modified: 
    llvm/lib/IR/Verifier.cpp
    llvm/test/DebugInfo/Generic/2009-11-03-InsertExtractValue.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 3fed0bf64b6e..e7187f46ed1c 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -2433,6 +2433,10 @@ void Verifier::visitFunction(const Function &F) {
                  "function must have a single !dbg attachment", &F, I.second);
         AssertDI(isa<DISubprogram>(I.second),
                  "function !dbg attachment must be a subprogram", &F, I.second);
+        AssertDI(cast<DISubprogram>(I.second)->isDistinct(),
+                 "function definition may only have a distinct !dbg attachment",
+                 &F);
+
         auto *SP = cast<DISubprogram>(I.second);
         const Function *&AttachedTo = DISubprogramAttachments[SP];
         AssertDI(!AttachedTo || AttachedTo == &F,

diff  --git a/llvm/test/DebugInfo/Generic/2009-11-03-InsertExtractValue.ll b/llvm/test/DebugInfo/Generic/2009-11-03-InsertExtractValue.ll
index 57ee7ebbb2cb..81bb5f2457ed 100644
--- a/llvm/test/DebugInfo/Generic/2009-11-03-InsertExtractValue.ll
+++ b/llvm/test/DebugInfo/Generic/2009-11-03-InsertExtractValue.ll
@@ -3,7 +3,7 @@
 !llvm.module.flags = !{!6}
 !llvm.dbg.cu = !{!5}
 
-!0 = !DISubprogram(name: "bar", linkageName: "_ZN3foo3barEv", line: 3, isLocal: false, isDefinition: false, virtualIndex: 6, flags: DIFlagProtected | DIFlagPrototyped, isOptimized: false, scopeLine: 3, file: !4, scope: !1, type: !2)
+!0 = distinct !DISubprogram(name: "bar", linkageName: "_ZN3foo3barEv", line: 3, isLocal: false, isDefinition: false, virtualIndex: 6, flags: DIFlagProtected | DIFlagPrototyped, isOptimized: false, scopeLine: 3, file: !4, scope: !1, type: !2)
 !1 = !DIFile(filename: "/foo", directory: "bar.cpp")
 !2 = !DISubroutineType(types: !3)
 !3 = !{null}

diff  --git a/llvm/test/Verifier/unique-disubprogram.ll b/llvm/test/Verifier/unique-disubprogram.ll
new file mode 100644
index 000000000000..b4789a9293f7
--- /dev/null
+++ b/llvm/test/Verifier/unique-disubprogram.ll
@@ -0,0 +1,16 @@
+; RUN: llvm-as -disable-output <%s 2>&1| FileCheck %s
+define i32 @_Z3foov() local_unnamed_addr !dbg !9 {
+  ret i32 5
+}
+!llvm.module.flags = !{!2}
+!llvm.dbg.cu = !{!5}
+!llvm.linker.options = !{}
+
+!2 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !6, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug)
+!6 = !DIFile(filename: "t.cpp", directory: "/")
+!7 = !{}
+; CHECK: function definition may only have a distinct !dbg attachment
+; CHECK: warning: ignoring invalid debug info
+!9 = !DISubprogram(name: "foo", linkageName: "_Z3foov", scope: !6, file: !6, line: 2, type: !11, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !7)
+!11 = !DISubroutineType(types: !7)