///alignstack(1))
const Attributes Hotpatch = 1<<29; ///< Function should have special
///'hotpatch' sequence in prologue
+const Attributes UWTable = 1<<30; ///< Function must be in a unwind
+ ///table
+
+/// Note that uwtable is about the ABI or the user mandating an entry in the
+/// unwind table. The nounwind attribute is about an exception passing by the
+/// function.
+/// In a theoretical system that uses tables for profiling and sjlj for
+/// exceptions, they would be fully independent. In a normal system that
+/// uses tables for both, the semantics are:
+/// nil = Needs an entry because an exception might pass by.
+/// nounwind = No need for an entry
+/// ehframe = Needs an entry because the ABI says so and because
+/// an exception might pass by.
+/// ehframe + nounwind = Needs an entry because the ABI says so.
/// @brief Attributes that only apply to function parameters.
const Attributes ParameterOnly = ByVal | Nest | StructRet | NoCapture;
const Attributes FunctionOnly = NoReturn | NoUnwind | ReadNone | ReadOnly |
NoInline | AlwaysInline | OptimizeForSize | StackProtect | StackProtectReq |
NoRedZone | NoImplicitFloat | Naked | InlineHint | StackAlignment |
- Hotpatch;
+ Hotpatch | UWTable;
/// @brief Parameter attributes that do not apply to vararg call arguments.
const Attributes VarArgsIncompatible = StructRet;
else removeFnAttr(Attribute::NoUnwind);
}
+ /// @brief True if the ABI mandates this function be in a unwind table.
+ bool hasUWTable() const {
+ return hasFnAttr(Attribute::UWTable);
+ }
+ void setHasUWTable(bool HasUWTable = true) {
+ if (HasUWTable)
+ addFnAttr(Attribute::UWTable);
+ else
+ removeFnAttr(Attribute::UWTable);
+ }
+
+ /// @brief True if this function needs in a unwind table.
+ bool needsUnwindTableEntry() const {
+ return hasUWTable() || !doesNotThrow();
+ }
+
/// @brief Determine if the function returns a structure through first
/// pointer argument.
bool hasStructRetAttr() const {
/// flag is hidden and is only for debugging the debug info.
extern bool JITEmitDebugInfoToDisk;
- /// UnwindTablesMandatory - This flag indicates that unwind tables should
- /// be emitted for all functions.
- extern bool UnwindTablesMandatory;
-
/// GuaranteedTailCallOpt - This flag is enabled when -tailcallopt is
/// specified on the commandline. When the flag is on, participating targets
/// will perform tail call optimization on all calls which use the fastcc
KEYWORD(nest);
KEYWORD(readnone);
KEYWORD(readonly);
+ KEYWORD(uwtable);
KEYWORD(inlinehint);
KEYWORD(noinline);
case lltok::kw_noreturn: Attrs |= Attribute::NoReturn; break;
case lltok::kw_nounwind: Attrs |= Attribute::NoUnwind; break;
+ case lltok::kw_uwtable: Attrs |= Attribute::UWTable; break;
case lltok::kw_noinline: Attrs |= Attribute::NoInline; break;
case lltok::kw_readnone: Attrs |= Attribute::ReadNone; break;
case lltok::kw_readonly: Attrs |= Attribute::ReadOnly; break;
kw_nest,
kw_readnone,
kw_readonly,
+ kw_uwtable,
kw_inlinehint,
kw_noinline,
/// being emitted immediately after the function entry point.
void ARMException::BeginFunction(const MachineFunction *MF) {
Asm->OutStreamer.EmitFnStart();
- if (!Asm->MF->getFunction()->doesNotThrow() || UnwindTablesMandatory)
+ if (Asm->MF->getFunction()->needsUnwindTableEntry())
Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin",
Asm->getFunctionNumber()));
}
/// EndFunction - Gather and emit post-function exception information.
///
void ARMException::EndFunction() {
- if (Asm->MF->getFunction()->doesNotThrow() && !UnwindTablesMandatory)
+ if (!Asm->MF->getFunction()->needsUnwindTableEntry())
Asm->OutStreamer.EmitCantUnwind();
else {
Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end",
}
AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
- if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI) {
- if (UnwindTablesMandatory)
- return CFI_M_EH;
-
- if (!MF->getFunction()->doesNotThrow())
- return CFI_M_EH;
- }
+ if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
+ MF->getFunction()->needsUnwindTableEntry())
+ return CFI_M_EH;
if (MMI->hasDebugInfo())
return CFI_M_Debug;
MachineModuleInfo &MMI = MF.getMMI();
DebugLoc dl;
bool needsFrameMoves = MMI.hasDebugInfo() ||
- !MF.getFunction()->doesNotThrow() ||
- UnwindTablesMandatory;
+ MF.getFunction()->needsUnwindTableEntry();
// Prepare for frame info.
MCSymbol *FrameLabel = 0;
bool JITExceptionHandling;
bool JITEmitDebugInfo;
bool JITEmitDebugInfoToDisk;
- bool UnwindTablesMandatory;
Reloc::Model RelocationModel;
CodeModel::Model CMModel;
bool GuaranteedTailCallOpt;
cl::desc("Emit debug info objfiles to disk"),
cl::location(JITEmitDebugInfoToDisk),
cl::init(false));
-static cl::opt<bool, true>
-EnableUnwindTables("unwind-tables",
- cl::desc("Generate unwinding tables for all functions"),
- cl::location(UnwindTablesMandatory),
- cl::init(false));
static cl::opt<llvm::Reloc::Model, true>
DefRelocationModel("relocation-model",
MachineModuleInfo &MMI = MF.getMMI();
X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
bool needsFrameMoves = MMI.hasDebugInfo() ||
- !Fn->doesNotThrow() || UnwindTablesMandatory;
+ Fn->needsUnwindTableEntry();
uint64_t MaxAlign = MFI->getMaxAlignment(); // Desired stack alignment.
uint64_t StackSize = MFI->getStackSize(); // Number of bytes to allocate.
bool HasFP = hasFP(MF);
}
bool XCoreRegisterInfo::needsFrameMoves(const MachineFunction &MF) {
- return MF.getMMI().hasDebugInfo() || !MF.getFunction()->doesNotThrow() ||
- UnwindTablesMandatory;
+ return MF.getMMI().hasDebugInfo() ||
+ MF.getFunction()->needsUnwindTableEntry();
}
const unsigned* XCoreRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF)
Result += "noreturn ";
if (Attrs & Attribute::NoUnwind)
Result += "nounwind ";
+ if (Attrs & Attribute::UWTable)
+ Result += "uwtable ";
if (Attrs & Attribute::InReg)
Result += "inreg ";
if (Attrs & Attribute::NoAlias)
-; RUN: llc < %s -disable-cfi -mtriple=i386-apple-darwin9 -relocation-model=pic -disable-fp-elim -unwind-tables | FileCheck %s
+; RUN: llc < %s -disable-cfi -mtriple=i386-apple-darwin9 -relocation-model=pic -disable-fp-elim | FileCheck %s
@.str = private constant [12 x i8] c"hello world\00", align 1 ; <[12 x i8]*> [#uses=1]
-define hidden void @func() nounwind ssp {
+define hidden void @func() nounwind ssp uwtable {
entry:
%0 = call i32 @puts(i8* getelementptr inbounds ([12 x i8]* @.str, i64 0, i64 0)) nounwind ; <i32> [#uses=0]
br label %return
declare i32 @puts(i8*)
-define hidden i32 @main() nounwind ssp {
+define hidden i32 @main() nounwind ssp uwtable {
entry:
%retval = alloca i32 ; <i32*> [#uses=1]
%"alloca point" = bitcast i32 0 to i32 ; <i32> [#uses=0]