Merging r276956:

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r276956 | majnemer | 2016-07-27 22:03:22 -0700 (Wed, 27 Jul 2016) | 6 lines

[CodeView] Don't crash on functions without subprograms

A function may have instructions annotated with debug info without
having a subprogram.

This fixes PR28747.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_39@277078 91177308-0d34-0410-b5e6-96231b3b80d8

Author: zmodem

lib/CodeGen/AsmPrinter/CodeViewDebug.cpp

@@ -214,10 +214,7 @@ TypeIndex CodeViewDebug::getScopeIndex(const DIScope *Scope) {
 }
 
 TypeIndex CodeViewDebug::getFuncIdForSubprogram(const DISubprogram *SP) {
-  // It's possible to ask for the FuncId of a function which doesn't have a
-  // subprogram: inlining a function with debug info into a function with none.
-  if (!SP)
-    return TypeIndex::None();
+  assert(SP);
 
   // Check if we've already translated this subprogram.
   auto I = TypeIndices.find({SP, nullptr});
@@ -621,11 +618,12 @@ void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
 
   std::string FuncName;
   auto *SP = GV->getSubprogram();
+  assert(SP);
   setCurrentSubprogram(SP);
 
   // If we have a display name, build the fully qualified name by walking the
   // chain of scopes.
-  if (SP != nullptr && !SP->getDisplayName().empty())
+  if (!SP->getDisplayName().empty())
     FuncName =
         getFullyQualifiedName(SP->getScope().resolve(), SP->getDisplayName());
 
@@ -864,7 +862,7 @@ void CodeViewDebug::collectVariableInfo(const DISubprogram *SP) {
 void CodeViewDebug::beginFunction(const MachineFunction *MF) {
   assert(!CurFn && "Can't process two functions at once!");
 
-  if (!Asm || !MMI->hasDebugInfo())
+  if (!Asm || !MMI->hasDebugInfo() || !MF->getFunction()->getSubprogram())
     return;
 
   DebugHandlerBase::beginFunction(MF);
@@ -1939,7 +1937,8 @@ void CodeViewDebug::beginInstruction(const MachineInstr *MI) {
   DebugHandlerBase::beginInstruction(MI);
 
   // Ignore DBG_VALUE locations and function prologue.
-  if (!Asm || MI->isDebugValue() || MI->getFlag(MachineInstr::FrameSetup))
+  if (!Asm || !CurFn || MI->isDebugValue() ||
+      MI->getFlag(MachineInstr::FrameSetup))
     return;
   DebugLoc DL = MI->getDebugLoc();
   if (DL == PrevInstLoc || !DL)

test/DebugInfo/COFF/inlining-same-name.ll

@@ -33,7 +33,7 @@
 target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-pc-windows-msvc"
 
-define void @main(i32* %i.i) {
+define void @main(i32* %i.i) !dbg !16 {
   store volatile i32 3, i32* %i.i, !dbg !6
   store volatile i32 3, i32* %i.i, !dbg !19
   ret void

test/DebugInfo/COFF/pr28747.ll

@@ -0,0 +1,44 @@
+; RUN: llc < %s | FileCheck %s
+
+; CHECK:             .section .debug$S,"dr"{{$}}
+; CHECK-NEXT:        .p2align 2
+; CHECK-NEXT:        .long 4
+; CHECK-NEXT:        .cv_filechecksums
+; CHECK-NEXT:        .cv_stringtable
+
+target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32"
+target triple = "i686-pc-windows-msvc18.0.0"
+
+define void @baz() {
+entry:
+  %x.i.i = alloca i32, align 4
+  call void @llvm.dbg.declare(metadata i32* %x.i.i, metadata !6, metadata !12), !dbg !13
+  store i32 5, i32* %x.i.i, align 4, !dbg !13
+  ret void
+}
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #0
+
+attributes #0 = { nounwind readnone }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+!llvm.ident = !{!5}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 4.0.0 (trunk 276756) (llvm/trunk 276952)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!1 = !DIFile(filename: "-", directory: "/")
+!2 = !{}
+!3 = !{i32 2, !"CodeView", i32 1}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{!"clang version 4.0.0 (trunk 276756) (llvm/trunk 276952)"}
+!6 = !DILocalVariable(name: "x", scope: !7, file: !8, line: 1, type: !11)
+!7 = distinct !DISubprogram(name: "foo", scope: !8, file: !8, line: 1, type: !9, isLocal: true, isDefinition: true, scopeLine: 1, isOptimized: false, unit: !0, variables: !2)
+!8 = !DIFile(filename: "<stdin>", directory: "/")
+!9 = !DISubroutineType(types: !10)
+!10 = !{null}
+!11 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!12 = !DIExpression()
+!13 = !DILocation(line: 1, column: 56, scope: !7, inlinedAt: !14)
+!14 = distinct !DILocation(line: 2, column: 52, scope: !15)
+!15 = distinct !DISubprogram(name: "bar", scope: !8, file: !8, line: 2, type: !9, isLocal: true, isDefinition: true, scopeLine: 2, isOptimized: false, unit: !0, variables: !2)