[llvm-commits] [llvm] r170279 - in /llvm/trunk: include/llvm/MC/ lib/CodeGen/AsmPrinter/ lib/MC/ lib/Target/Mips/MCTargetDesc/ test/CodeGen/Mips/ tools/lto/
Reed Kotler
rkotler at mips.com
Sat Dec 15 20:00:46 PST 2012
Author: rkotler
Date: Sat Dec 15 22:00:45 2012
New Revision: 170279
URL: http://llvm.org/viewvc/llvm-project?rev=170279&view=rev
Log:
This patch is needed to make c++ exceptions work for mips16.
Mips16 is really a processor decoding mode (ala thumb 1) and in the same
program, mips16 and mips32 functions can exist and can call each other.
If a jal type instruction encounters an address with the lower bit set, then
the processor switches to mips16 mode (if it is not already in it). If the
lower bit is not set, then it switches to mips32 mode.
The linker knows which functions are mips16 and which are mips32.
When relocation is performed on code labels, this lower order bit is
set if the code label is a mips16 code label.
In general this works just fine, however when creating exception handling
tables and dwarf, there are cases where you don't want this lower order
bit added in.
This has been traditionally distinguished in gas assembly source by using a
different syntax for the label.
lab1: ; this will cause the lower order bit to be added
lab2=. ; this will not cause the lower order bit to be added
In some cases, it does not matter because in dwarf and debug tables
the difference of two labels is used and in that case the lower order
bits subtract each other out.
To fix this, I have added to mcstreamer the notion of a debuglabel.
The default is for label and debug label to be the same. So calling
EmitLabel and EmitDebugLabel produce the same result.
For various reasons, there is only one set of labels that needs to be
modified for the mips exceptions to work. These are the "$eh_func_beginXXX"
labels.
Mips overrides the debug label suffix from ":" to "=." .
This initial patch fixes exceptions. More changes most likely
will be needed to DwarfCFException to make all of this work
for actual debugging. These changes will be to emit debug labels in some
places where a simple label is emitted now.
Some historical discussion on this from gcc can be found at:
http://gcc.gnu.org/ml/gcc-patches/2008-08/msg00623.html
http://gcc.gnu.org/ml/gcc-patches/2008-11/msg01273.html
Added:
llvm/trunk/test/CodeGen/Mips/mips16ex.ll
Modified:
llvm/trunk/include/llvm/MC/MCAsmInfo.h
llvm/trunk/include/llvm/MC/MCELFStreamer.h
llvm/trunk/include/llvm/MC/MCObjectStreamer.h
llvm/trunk/include/llvm/MC/MCStreamer.h
llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp
llvm/trunk/lib/MC/MCAsmInfo.cpp
llvm/trunk/lib/MC/MCAsmStreamer.cpp
llvm/trunk/lib/MC/MCELFStreamer.cpp
llvm/trunk/lib/MC/MCMachOStreamer.cpp
llvm/trunk/lib/MC/MCNullStreamer.cpp
llvm/trunk/lib/MC/MCObjectStreamer.cpp
llvm/trunk/lib/MC/MCPureStreamer.cpp
llvm/trunk/lib/MC/MCStreamer.cpp
llvm/trunk/lib/MC/WinCOFFStreamer.cpp
llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsMCAsmInfo.cpp
llvm/trunk/tools/lto/LTOModule.cpp
Modified: llvm/trunk/include/llvm/MC/MCAsmInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCAsmInfo.h?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCAsmInfo.h (original)
+++ llvm/trunk/include/llvm/MC/MCAsmInfo.h Sat Dec 15 22:00:45 2012
@@ -102,6 +102,9 @@
/// LabelSuffix - This is appended to emitted labels.
const char *LabelSuffix; // Defaults to ":"
+ /// LabelSuffix - This is appended to emitted labels.
+ const char *DebugLabelSuffix; // Defaults to ":"
+
/// GlobalPrefix - If this is set to a non-empty string, it is prepended
/// onto all global symbols. This is often used for "_" or ".".
const char *GlobalPrefix; // Defaults to ""
@@ -426,6 +429,11 @@
const char *getLabelSuffix() const {
return LabelSuffix;
}
+
+ const char *getDebugLabelSuffix() const {
+ return DebugLabelSuffix;
+ }
+
const char *getGlobalPrefix() const {
return GlobalPrefix;
}
Modified: llvm/trunk/include/llvm/MC/MCELFStreamer.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCELFStreamer.h?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCELFStreamer.h (original)
+++ llvm/trunk/include/llvm/MC/MCELFStreamer.h Sat Dec 15 22:00:45 2012
@@ -47,6 +47,7 @@
virtual void InitSections();
virtual void ChangeSection(const MCSection *Section);
virtual void EmitLabel(MCSymbol *Symbol);
+ virtual void EmitDebugLabel(MCSymbol *Symbol);
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
virtual void EmitThumbFunc(MCSymbol *Func);
virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
Modified: llvm/trunk/include/llvm/MC/MCObjectStreamer.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCObjectStreamer.h?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCObjectStreamer.h (original)
+++ llvm/trunk/include/llvm/MC/MCObjectStreamer.h Sat Dec 15 22:00:45 2012
@@ -69,6 +69,7 @@
/// @{
virtual void EmitLabel(MCSymbol *Symbol);
+ virtual void EmitDebugLabel(MCSymbol *Symbol);
virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
unsigned AddrSpace);
Modified: llvm/trunk/include/llvm/MC/MCStreamer.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCStreamer.h?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCStreamer.h (original)
+++ llvm/trunk/include/llvm/MC/MCStreamer.h Sat Dec 15 22:00:45 2012
@@ -244,6 +244,8 @@
/// used in an assignment.
virtual void EmitLabel(MCSymbol *Symbol);
+ virtual void EmitDebugLabel(MCSymbol *Symbol);
+
virtual void EmitEHSymAttributes(const MCSymbol *Symbol,
MCSymbol *EHSymbol);
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp Sat Dec 15 22:00:45 2012
@@ -122,8 +122,9 @@
const MCSymbol *Sym = TLOF.getCFIPersonalitySymbol(Per, Asm->Mang, MMI);
Asm->OutStreamer.EmitCFIPersonality(Sym, PerEncoding);
- Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin",
- Asm->getFunctionNumber()));
+ Asm->OutStreamer.EmitDebugLabel
+ (Asm->GetTempSymbol("eh_func_begin",
+ Asm->getFunctionNumber()));
// Provide LSDA information.
if (!shouldEmitLSDA)
Modified: llvm/trunk/lib/MC/MCAsmInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCAsmInfo.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCAsmInfo.cpp (original)
+++ llvm/trunk/lib/MC/MCAsmInfo.cpp Sat Dec 15 22:00:45 2012
@@ -37,6 +37,7 @@
CommentColumn = 40;
CommentString = "#";
LabelSuffix = ":";
+ DebugLabelSuffix = ":";
GlobalPrefix = "";
PrivateGlobalPrefix = ".";
LinkerPrivateGlobalPrefix = "";
Modified: llvm/trunk/lib/MC/MCAsmStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCAsmStreamer.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCAsmStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCAsmStreamer.cpp Sat Dec 15 22:00:45 2012
@@ -135,6 +135,8 @@
}
virtual void EmitLabel(MCSymbol *Symbol);
+ virtual void EmitDebugLabel(MCSymbol *Symbol);
+
virtual void EmitEHSymAttributes(const MCSymbol *Symbol,
MCSymbol *EHSymbol);
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
@@ -345,6 +347,14 @@
EmitEOL();
}
+void MCAsmStreamer::EmitDebugLabel(MCSymbol *Symbol) {
+ assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
+ MCStreamer::EmitDebugLabel(Symbol);
+
+ OS << *Symbol << MAI.getDebugLabelSuffix();
+ EmitEOL();
+}
+
void MCAsmStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
switch (Flag) {
case MCAF_SyntaxUnified: OS << "\t.syntax unified"; break;
Modified: llvm/trunk/lib/MC/MCELFStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCELFStreamer.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCELFStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCELFStreamer.cpp Sat Dec 15 22:00:45 2012
@@ -86,6 +86,10 @@
MCELF::SetType(SD, ELF::STT_TLS);
}
+void MCELFStreamer::EmitDebugLabel(MCSymbol *Symbol) {
+ EmitLabel(Symbol);
+}
+
void MCELFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
switch (Flag) {
case MCAF_SyntaxUnified: return; // no-op here.
Modified: llvm/trunk/lib/MC/MCMachOStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCMachOStreamer.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCMachOStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCMachOStreamer.cpp Sat Dec 15 22:00:45 2012
@@ -43,6 +43,7 @@
virtual void InitSections();
virtual void EmitLabel(MCSymbol *Symbol);
+ virtual void EmitDebugLabel(MCSymbol *Symbol);
virtual void EmitEHSymAttributes(const MCSymbol *Symbol,
MCSymbol *EHSymbol);
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
@@ -130,6 +131,9 @@
SD.setFlags(SD.getFlags() & ~SF_ReferenceTypeMask);
}
+void MCMachOStreamer::EmitDebugLabel(MCSymbol *Symbol) {
+ EmitLabel(Symbol);
+}
void MCMachOStreamer::EmitDataRegion(DataRegionData::KindTy Kind) {
if (!getAssembler().getBackend().hasDataInCodeSupport())
return;
Modified: llvm/trunk/lib/MC/MCNullStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCNullStreamer.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCNullStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCNullStreamer.cpp Sat Dec 15 22:00:45 2012
@@ -35,7 +35,9 @@
assert(getCurrentSection() && "Cannot emit before setting section!");
Symbol->setSection(*getCurrentSection());
}
-
+ virtual void EmitDebugLabel(MCSymbol *Symbol) {
+ EmitLabel(Symbol);
+ }
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) {}
virtual void EmitThumbFunc(MCSymbol *Func) {}
Modified: llvm/trunk/lib/MC/MCObjectStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCObjectStreamer.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCObjectStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCObjectStreamer.cpp Sat Dec 15 22:00:45 2012
@@ -134,6 +134,10 @@
SD.setOffset(F->getContents().size());
}
+void MCObjectStreamer::EmitDebugLabel(MCSymbol *Symbol) {
+ EmitLabel(Symbol);
+}
+
void MCObjectStreamer::EmitULEB128Value(const MCExpr *Value) {
int64_t IntValue;
if (Value->EvaluateAsAbsolute(IntValue, getAssembler())) {
Modified: llvm/trunk/lib/MC/MCPureStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCPureStreamer.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCPureStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCPureStreamer.cpp Sat Dec 15 22:00:45 2012
@@ -37,6 +37,7 @@
virtual void InitSections();
virtual void EmitLabel(MCSymbol *Symbol);
+ virtual void EmitDebugLabel(MCSymbol *Symbol);
virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
uint64_t Size = 0, unsigned ByteAlignment = 0);
virtual void EmitBytes(StringRef Data, unsigned AddrSpace);
@@ -134,6 +135,7 @@
SD.setOffset(F->getContents().size());
}
+
void MCPureStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
uint64_t Size, unsigned ByteAlignment) {
report_fatal_error("not yet implemented in pure streamer");
Modified: llvm/trunk/lib/MC/MCStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCStreamer.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCStreamer.cpp (original)
+++ llvm/trunk/lib/MC/MCStreamer.cpp Sat Dec 15 22:00:45 2012
@@ -195,6 +195,13 @@
LastSymbol = Symbol;
}
+void MCStreamer::EmitDebugLabel(MCSymbol *Symbol) {
+ assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
+ assert(getCurrentSection() && "Cannot emit before setting section!");
+ Symbol->setSection(*getCurrentSection());
+ LastSymbol = Symbol;
+}
+
void MCStreamer::EmitCompactUnwindEncoding(uint32_t CompactUnwindEncoding) {
EnsureValidFrame();
MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
Modified: llvm/trunk/lib/MC/WinCOFFStreamer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/WinCOFFStreamer.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/MC/WinCOFFStreamer.cpp (original)
+++ llvm/trunk/lib/MC/WinCOFFStreamer.cpp Sat Dec 15 22:00:45 2012
@@ -51,6 +51,7 @@
virtual void InitSections();
virtual void EmitLabel(MCSymbol *Symbol);
+ virtual void EmitDebugLabel(MCSymbol *Symbol);
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
virtual void EmitThumbFunc(MCSymbol *Func);
virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
@@ -176,6 +177,9 @@
MCObjectStreamer::EmitLabel(Symbol);
}
+void WinCOFFStreamer::EmitDebugLabel(MCSymbol *Symbol) {
+ EmitLabel(Symbol);
+}
void WinCOFFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
llvm_unreachable("not implemented");
}
Modified: llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsMCAsmInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsMCAsmInfo.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsMCAsmInfo.cpp (original)
+++ llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsMCAsmInfo.cpp Sat Dec 15 22:00:45 2012
@@ -34,7 +34,7 @@
GPRel32Directive = "\t.gpword\t";
GPRel64Directive = "\t.gpdword\t";
WeakRefDirective = "\t.weak\t";
-
+ DebugLabelSuffix = "=.";
SupportsDebugInformation = true;
ExceptionsType = ExceptionHandling::DwarfCFI;
HasLEB128 = true;
Added: llvm/trunk/test/CodeGen/Mips/mips16ex.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Mips/mips16ex.ll?rev=170279&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/Mips/mips16ex.ll (added)
+++ llvm/trunk/test/CodeGen/Mips/mips16ex.ll Sat Dec 15 22:00:45 2012
@@ -0,0 +1,87 @@
+; RUN: llc -march=mipsel -mcpu=mips16 -relocation-model=pic -O3 < %s | FileCheck %s -check-prefix=16
+
+;16: $eh_func_begin0=.
+ at .str = private unnamed_addr constant [7 x i8] c"hello\0A\00", align 1
+ at _ZTIi = external constant i8*
+ at .str1 = private unnamed_addr constant [15 x i8] c"exception %i \0A\00", align 1
+
+define i32 @main() {
+entry:
+ %retval = alloca i32, align 4
+ %exn.slot = alloca i8*
+ %ehselector.slot = alloca i32
+ %e = alloca i32, align 4
+ store i32 0, i32* %retval
+ %call = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([7 x i8]* @.str, i32 0, i32 0))
+ %exception = call i8* @__cxa_allocate_exception(i32 4) nounwind
+ %0 = bitcast i8* %exception to i32*
+ store i32 20, i32* %0
+ invoke void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) noreturn
+ to label %unreachable unwind label %lpad
+
+lpad: ; preds = %entry
+ %1 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
+ catch i8* bitcast (i8** @_ZTIi to i8*)
+ %2 = extractvalue { i8*, i32 } %1, 0
+ store i8* %2, i8** %exn.slot
+ %3 = extractvalue { i8*, i32 } %1, 1
+ store i32 %3, i32* %ehselector.slot
+ br label %catch.dispatch
+
+catch.dispatch: ; preds = %lpad
+ %sel = load i32* %ehselector.slot
+ %4 = call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*)) nounwind
+ %matches = icmp eq i32 %sel, %4
+ br i1 %matches, label %catch, label %eh.resume
+
+catch: ; preds = %catch.dispatch
+ %exn = load i8** %exn.slot
+ %5 = call i8* @__cxa_begin_catch(i8* %exn) nounwind
+ %6 = bitcast i8* %5 to i32*
+ %exn.scalar = load i32* %6
+ store i32 %exn.scalar, i32* %e, align 4
+ %7 = load i32* %e, align 4
+ %call2 = invoke i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([15 x i8]* @.str1, i32 0, i32 0), i32 %7)
+ to label %invoke.cont unwind label %lpad1
+
+invoke.cont: ; preds = %catch
+ call void @__cxa_end_catch() nounwind
+ br label %try.cont
+
+try.cont: ; preds = %invoke.cont
+ ret i32 0
+
+lpad1: ; preds = %catch
+ %8 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
+ cleanup
+ %9 = extractvalue { i8*, i32 } %8, 0
+ store i8* %9, i8** %exn.slot
+ %10 = extractvalue { i8*, i32 } %8, 1
+ store i32 %10, i32* %ehselector.slot
+ call void @__cxa_end_catch() nounwind
+ br label %eh.resume
+
+eh.resume: ; preds = %lpad1, %catch.dispatch
+ %exn3 = load i8** %exn.slot
+ %sel4 = load i32* %ehselector.slot
+ %lpad.val = insertvalue { i8*, i32 } undef, i8* %exn3, 0
+ %lpad.val5 = insertvalue { i8*, i32 } %lpad.val, i32 %sel4, 1
+ resume { i8*, i32 } %lpad.val5
+
+unreachable: ; preds = %entry
+ unreachable
+}
+
+declare i32 @printf(i8*, ...)
+
+declare i8* @__cxa_allocate_exception(i32)
+
+declare i32 @__gxx_personality_v0(...)
+
+declare void @__cxa_throw(i8*, i8*, i8*)
+
+declare i32 @llvm.eh.typeid.for(i8*) nounwind readnone
+
+declare i8* @__cxa_begin_catch(i8*)
+
+declare void @__cxa_end_catch()
Modified: llvm/trunk/tools/lto/LTOModule.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/lto/LTOModule.cpp?rev=170279&r1=170278&r2=170279&view=diff
==============================================================================
--- llvm/trunk/tools/lto/LTOModule.cpp (original)
+++ llvm/trunk/tools/lto/LTOModule.cpp Sat Dec 15 22:00:45 2012
@@ -745,6 +745,9 @@
Symbol->setSection(*getCurrentSection());
markDefined(*Symbol);
}
+ virtual void EmitDebugLabel(MCSymbol *Symbol) {
+ EmitLabel(Symbol);
+ }
virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
// FIXME: should we handle aliases?
markDefined(*Symbol);
More information about the llvm-commits
mailing list