Centralize handling of the eh_begin and eh_end labels.

This removes a bit of duplicated code and more importantly, remembers the
labels so that they don't need to be looked up by name.

This in turn allows for any name to be used and avoids a crash if the name
we wanted was already taken.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230772 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/CodeGen/AsmPrinter.h b/include/llvm/CodeGen/AsmPrinter.h
index ac224d8..feebe92 100644 (file)
--- a/include/llvm/CodeGen/AsmPrinter.h
+++ b/include/llvm/CodeGen/AsmPrinter.h
@@ -103,6 +103,9 @@ public:
   DenseMap<const MCSymbol *, GOTEquivUsePair> GlobalGOTEquivs;
 
 private:
+  MCSymbol *CurrentFnBegin;
+  MCSymbol *CurrentFnEnd;
+
   // The garbage collection metadata printer table.
   void *GCMetadataPrinters; // Really a DenseMap.
 
@@ -146,6 +149,9 @@ public:
   ///
   unsigned getFunctionNumber() const;
 
+  MCSymbol *getFunctionBegin() const { return CurrentFnBegin; }
+  MCSymbol *getFunctionEnd() const { return CurrentFnEnd; }
+
   /// Return information about object file lowering.
   const TargetLoweringObjectFile &getObjFileLowering() const;
 
@@ -331,6 +337,8 @@ public:
   /// Return an assembler temporary label with the specified stem.
   MCSymbol *GetTempSymbol(const Twine &Name) const;
 
+  MCSymbol *createTempSymbol(const Twine &Name, unsigned ID) const;
+
   /// Return the MCSymbol for a private symbol with global value name as its
   /// base, with the specified suffix.
   MCSymbol *getSymbolWithGlobalValueBase(const GlobalValue *GV,

diff --git a/include/llvm/MC/MCContext.h b/include/llvm/MC/MCContext.h
index cd96dfd..0a97744 100644 (file)
--- a/include/llvm/MC/MCContext.h
+++ b/include/llvm/MC/MCContext.h
@@ -215,6 +215,8 @@ namespace llvm {
     /// with a unique but unspecified name.
     MCSymbol *CreateTempSymbol();
 
+    MCSymbol *createTempSymbol(const Twine &Name);
+
     /// getUniqueSymbolID() - Return a unique identifier for use in constructing
     /// symbol names.
     unsigned getUniqueSymbolID() { return NextUniqueID++; }

diff --git a/lib/CodeGen/AsmPrinter/ARMException.cpp b/lib/CodeGen/AsmPrinter/ARMException.cpp
index 6fe75ad..119aa3a 100644 (file)
--- a/lib/CodeGen/AsmPrinter/ARMException.cpp
+++ b/lib/CodeGen/AsmPrinter/ARMException.cpp
@@ -58,8 +58,6 @@ void ARMException::endModule() {
 void ARMException::beginFunction(const MachineFunction *MF) {
   if (Asm->MAI->getExceptionHandlingType() == ExceptionHandling::ARM)
     getTargetStreamer().emitFnStart();
-  Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin",
-                                                Asm->getFunctionNumber()));
   // See if we need call frame info.
   AsmPrinter::CFIMoveType MoveType = Asm->needsCFIMoves();
   assert(MoveType != AsmPrinter::CFI_M_EH &&
@@ -84,8 +82,6 @@ void ARMException::endFunction(const MachineFunction *) {
       MMI->getLandingPads().empty())
     ATS.emitCantUnwind();
   else {
-    Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end",
-                                                  Asm->getFunctionNumber()));
     if (!MMI->getLandingPads().empty()) {
       // Emit references to personality.
       if (const Function *Personality = MMI->getPersonality()) {

diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 988381d..b94278f 100644 (file)
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -109,6 +109,8 @@ AsmPrinter::AsmPrinter(TargetMachine &tm, std::unique_ptr<MCStreamer> Streamer)
   LI = nullptr;
   MF = nullptr;
   CurrentFnSym = CurrentFnSymForSize = nullptr;
+  CurrentFnBegin = nullptr;
+  CurrentFnEnd = nullptr;
   GCMetadataPrinters = nullptr;
   VerboseAsm = OutStreamer.isVerboseAsm();
 }
@@ -554,6 +556,19 @@ void AsmPrinter::EmitFunctionHeader() {
     OutStreamer.EmitLabel(DeadBlockSyms[i]);
   }
 
+  if (!MMI->getLandingPads().empty()) {
+    CurrentFnBegin = createTempSymbol("eh_func_begin", getFunctionNumber());
+
+    if (MAI->useAssignmentForEHBegin()) {
+      MCSymbol *CurPos = OutContext.CreateTempSymbol();
+      OutStreamer.EmitLabel(CurPos);
+      OutStreamer.EmitAssignment(CurrentFnBegin,
+                                 MCSymbolRefExpr::Create(CurPos, OutContext));
+    } else {
+      OutStreamer.EmitLabel(CurrentFnBegin);
+    }
+  }
+
   // Emit pre-function debug and/or EH information.
   for (const HandlerInfo &HI : Handlers) {
     NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
@@ -867,6 +882,12 @@ void AsmPrinter::EmitFunctionBody() {
   // Emit target-specific gunk after the function body.
   EmitFunctionBodyEnd();
 
+  if (!MMI->getLandingPads().empty()) {
+    // Create a symbol for the end of function.
+    CurrentFnEnd = createTempSymbol("eh_func_end", getFunctionNumber());
+    OutStreamer.EmitLabel(CurrentFnEnd);
+  }
+
   // If the target wants a .size directive for the size of the function, emit
   // it.
   if (MAI->hasDotTypeDotSizeDirective()) {
@@ -2273,6 +2294,9 @@ MCSymbol *AsmPrinter::GetTempSymbol(const Twine &Name) const {
                                       Name);
 }
 
+MCSymbol *AsmPrinter::createTempSymbol(const Twine &Name, unsigned ID) const {
+  return OutContext.createTempSymbol(Name + Twine(ID));
+}
 
 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
   return MMI->getAddrLabelSymbol(BA->getBasicBlock());

diff --git a/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp b/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp
index f45b24c..128ec82 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp
@@ -113,18 +113,6 @@ void DwarfCFIException::beginFunction(const MachineFunction *MF) {
       TLOF.getCFIPersonalitySymbol(Per, *Asm->Mang, Asm->TM, MMI);
   Asm->OutStreamer.EmitCFIPersonality(Sym, PerEncoding);
 
-  MCSymbol *EHBegin =
-      Asm->GetTempSymbol("eh_func_begin", Asm->getFunctionNumber());
-  if (Asm->MAI->useAssignmentForEHBegin()) {
-    MCContext &Ctx = Asm->OutContext;
-    MCSymbol *CurPos = Ctx.CreateTempSymbol();
-    Asm->OutStreamer.EmitLabel(CurPos);
-    Asm->OutStreamer.EmitAssignment(EHBegin,
-                                    MCSymbolRefExpr::Create(CurPos, Ctx));
-  } else {
-    Asm->OutStreamer.EmitLabel(EHBegin);
-  }
-
   // Provide LSDA information.
   if (!shouldEmitLSDA)
     return;
@@ -145,9 +133,6 @@ void DwarfCFIException::endFunction(const MachineFunction *) {
   if (!shouldEmitPersonality)
     return;
 
-  Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end",
-                                                Asm->getFunctionNumber()));
-
   // Map all labels and get rid of any dead landing pads.
   MMI->TidyLandingPads();
 

diff --git a/lib/CodeGen/AsmPrinter/EHStreamer.cpp b/lib/CodeGen/AsmPrinter/EHStreamer.cpp
index 4841814..e4084db 100644 (file)
--- a/lib/CodeGen/AsmPrinter/EHStreamer.cpp
+++ b/lib/CodeGen/AsmPrinter/EHStreamer.cpp
@@ -552,16 +552,14 @@ void EHStreamer::emitExceptionTable() {
          I = CallSites.begin(), E = CallSites.end(); I != E; ++I) {
       const CallSiteEntry &S = *I;
 
-      MCSymbol *EHFuncBeginSym =
-        Asm->GetTempSymbol("eh_func_begin", Asm->getFunctionNumber());
+      MCSymbol *EHFuncBeginSym = Asm->getFunctionBegin();
 
       MCSymbol *BeginLabel = S.BeginLabel;
       if (!BeginLabel)
         BeginLabel = EHFuncBeginSym;
       MCSymbol *EndLabel = S.EndLabel;
       if (!EndLabel)
-        EndLabel = Asm->GetTempSymbol("eh_func_end", Asm->getFunctionNumber());
-
+        EndLabel = Asm->getFunctionEnd();
 
       // Offset of the call site relative to the previous call site, counted in
       // number of 16-byte bundles. The first call site is counted relative to

diff --git a/lib/CodeGen/AsmPrinter/Win64Exception.cpp b/lib/CodeGen/AsmPrinter/Win64Exception.cpp
index 2b03877..356a351 100644 (file)
--- a/lib/CodeGen/AsmPrinter/Win64Exception.cpp
+++ b/lib/CodeGen/AsmPrinter/Win64Exception.cpp
@@ -80,9 +80,6 @@ void Win64Exception::beginFunction(const MachineFunction *MF) {
   const MCSymbol *PersHandlerSym =
       TLOF.getCFIPersonalitySymbol(Per, *Asm->Mang, Asm->TM, MMI);
   Asm->OutStreamer.EmitWinEHHandler(PersHandlerSym, true, true);
-
-  Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin",
-                                                Asm->getFunctionNumber()));
 }
 
 /// endFunction - Gather and emit post-function exception information.
@@ -91,9 +88,6 @@ void Win64Exception::endFunction(const MachineFunction *) {
   if (!shouldEmitPersonality && !shouldEmitMoves)
     return;
 
-  Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end",
-                                                Asm->getFunctionNumber()));
-
   // Map all labels and get rid of any dead landing pads.
   MMI->TidyLandingPads();
 
@@ -170,10 +164,8 @@ void Win64Exception::emitCSpecificHandlerTable() {
   SmallVector<CallSiteEntry, 64> CallSites;
   computeCallSiteTable(CallSites, LandingPads, FirstActions);
 
-  MCSymbol *EHFuncBeginSym =
-      Asm->GetTempSymbol("eh_func_begin", Asm->getFunctionNumber());
-  MCSymbol *EHFuncEndSym =
-      Asm->GetTempSymbol("eh_func_end", Asm->getFunctionNumber());
+  MCSymbol *EHFuncBeginSym = Asm->getFunctionBegin();
+  MCSymbol *EHFuncEndSym = Asm->getFunctionEnd();
 
   // Emit the number of table entries.
   unsigned NumEntries = 0;

diff --git a/lib/MC/MCContext.cpp b/lib/MC/MCContext.cpp
index 721edd4..b2c6958 100644 (file)
--- a/lib/MC/MCContext.cpp
+++ b/lib/MC/MCContext.cpp
@@ -160,6 +160,12 @@ MCSymbol *MCContext::CreateSymbol(StringRef Name) {
   return Result;
 }
 
+MCSymbol *MCContext::createTempSymbol(const Twine &Name) {
+  SmallString<128> NameSV;
+  raw_svector_ostream(NameSV) << MAI->getPrivateGlobalPrefix() << Name;
+  return CreateSymbol(NameSV);
+}
+
 MCSymbol *MCContext::GetOrCreateSymbol(const Twine &Name) {
   SmallString<128> NameSV;
   return GetOrCreateSymbol(Name.toStringRef(NameSV));

diff --git a/test/CodeGen/Mips/mips16ex.ll b/test/CodeGen/Mips/mips16ex.ll
index a1a9919..3f70c72 100644 (file)
--- a/test/CodeGen/Mips/mips16ex.ll
+++ b/test/CodeGen/Mips/mips16ex.ll
@@ -1,8 +1,10 @@
 ; RUN: llc  -march=mipsel -mcpu=mips16 -relocation-model=pic -O3 < %s | FileCheck %s -check-prefix=16
 
-;16: .cfi_personality
+;16: main:
 ;16-NEXT: [[TMP:.*]]:
 ;16-NEXT: $eh_func_begin0 = ([[TMP]])
+;16-NEXT: .cfi_startproc
+;16-NEXT: .cfi_personality
 @.str = private unnamed_addr constant [7 x i8] c"hello\0A\00", align 1
 @_ZTIi = external constant i8*
 @.str1 = private unnamed_addr constant [15 x i8] c"exception %i \0A\00", align 1

diff --git a/test/CodeGen/X86/eh-label.ll b/test/CodeGen/X86/eh-label.ll
new file mode 100644 (file)
index 0000000..7019b45
--- /dev/null
+++ b/test/CodeGen/X86/eh-label.ll
@@ -0,0 +1,24 @@
+; RUN: llc < %s -mtriple=x86_64-pc-linux | FileCheck %s
+; Test that we don't crashe if the .Leh_func_end0 name is taken.
+
+declare void @g()
+
+define void @f() {
+bb0:
+  call void asm ".Leh_func_end0:", ""()
+; CHECK: #APP
+; CHECK-NEXT: .Leh_func_end0:
+; CHECK-NEXT: #NO_APP
+
+  invoke void @g() to label %bb2 unwind label %bb1
+bb1:
+  landingpad { i8*, i32 } personality i8* bitcast (void ()* @g to i8*)
+          catch i8* null
+  call void @g()
+  ret void
+bb2:
+  ret void
+
+; CHECK: [[END:.Leh_func_end.*]]:
+; CHECK: .long [[END]]-
+}

diff --git a/test/CodeGen/X86/global-sections.ll b/test/CodeGen/X86/global-sections.ll
index 4ee8353..6369539 100644 (file)
--- a/test/CodeGen/X86/global-sections.ll
+++ b/test/CodeGen/X86/global-sections.ll
@@ -84,8 +84,8 @@ bb7:
 }
 
 ; DARWIN64: _F3:
-; DARWIN64: .cfi_endproc
-; DARWIN64-NEXT: Leh_func_end
+; DARWIN64: Leh_func_end
+; DARWIN64-NEXT: .cfi_endproc
 ; DARWIN64-NEXT: .section        __TEXT,__gcc_except_tab
 ; DARWIN64-NOT: .section
 ; DARWIN64: .section        __TEXT,__text,regular,pure_instructions

diff --git a/test/CodeGen/X86/patchpoint-invoke.ll b/test/CodeGen/X86/patchpoint-invoke.ll
index 192cacc..8123f94 100644 (file)
--- a/test/CodeGen/X86/patchpoint-invoke.ll
+++ b/test/CodeGen/X86/patchpoint-invoke.ll
@@ -5,8 +5,8 @@
 define i64 @patchpoint_invoke(i64 %p1, i64 %p2) {
 entry:
 ; CHECK-LABEL: patchpoint_invoke:
+; CHECK-NEXT:  [[FUNC_BEGIN:.L.*]]:
 ; CHECK-NEXT: .cfi_startproc
-; CHECK:      [[FUNC_BEGIN:.L.*]]:
 ; CHECK:      .cfi_lsda 3, [[EXCEPTION_LABEL:.L[^ ]*]]
 ; CHECK:      pushq %rbp
 

diff --git a/test/CodeGen/XCore/exception.ll b/test/CodeGen/XCore/exception.ll
index fec83eb..dcff0d6 100644 (file)
--- a/test/CodeGen/XCore/exception.ll
+++ b/test/CodeGen/XCore/exception.ll
@@ -39,10 +39,10 @@ entry:
   unreachable
 }
 
-; CHECK-LABEL: fn_catch
+; CHECK-LABEL: fn_catch:
+; CHECK-NEXT: [[START:.L[a-zA-Z0-9_]+]]
 ; CHECK: .cfi_startproc
 ; CHECK: .cfi_personality 0, __gxx_personality_v0
-; CHECK: [[START:.L[a-zA-Z0-9_]+]]
 ; CHECK: .cfi_lsda 0, [[LSDA:.L[a-zA-Z0-9_]+]]
 ; CHECK: entsp 4
 ; CHECK: .cfi_def_cfa_offset 16
@@ -91,8 +91,8 @@ lpad:
 ; CHECK: bf r0, [[RETURN]]
 ; CHECK: mov r0, r4
 ; CHECK: bl _Unwind_Resume
-; CHECK: .cfi_endproc
 ; CHECK: [[END:.L[a-zA-Z0-9_]+]]
+; CHECK: .cfi_endproc
   %6 = icmp eq i32 %5, %2
   br i1 %6, label %Resume, label %Exit
 Resume: