which is supposed to consistently raise SIGTRAP across all systems. In contrast,
__builtin_trap() behave differently on different systems. e.g. it raises SIGTRAP on ARM, and
SIGILL on X86. The purpose of __builtin_debugtrap() is to consistently provide "trap"
functionality, in the mean time preserve the compatibility with on gcc on __builtin_trap().
The X86 backend is already able to handle debugtrap(). This patch is to:
1) make front-end recognize "__builtin_debugtrap()" (emboddied in the one-line change to Clang).
2) In DAG legalization phase, by default, "debugtrap" will be replaced with "trap", which
make the __builtin_debugtrap() "available" to all existing ports without the hassle of
changing their code.
3) If trap-function is specified (via -trap-func=xyz to llc), both __builtin_debugtrap() and
__builtin_trap() will be expanded into the function call of the specified trap function.
This behavior may need change in the future.
The provided testing-case is to make sure 2) and 3) are working for ARM port, and we
already have a testing case for x86.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166300
91177308-0d34-0410-b5e6-
96231b3b80d8
GCCBuiltin<"__builtin_flt_rounds">;
def int_trap : Intrinsic<[], [], [IntrNoReturn]>,
GCCBuiltin<"__builtin_trap">;
-def int_debugtrap : Intrinsic<[]>,
+def int_debugtrap : Intrinsic<[], [], [IntrNoReturn]>,
GCCBuiltin<"__builtin_debugtrap">;
// NOP: calls/invokes to this intrinsic are removed by codegen
if (Action == TargetLowering::Legal)
Action = TargetLowering::Custom;
break;
+ case ISD::DEBUGTRAP:
+ Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
+ if (Action == TargetLowering::Expand) {
+ // replace ISD::DEBUGTRAP with ISD::TRAP
+ SDValue NewVal;
+ NewVal = DAG.getNode (ISD::TRAP, Node->getDebugLoc(), Node->getVTList(),
+ Node->getOperand(0));
+ ReplaceNode(Node, NewVal.getNode());
+ LegalizeOp(NewVal.getNode());
+ return;
+ }
+ break;
+
default:
if (Node->getOpcode() >= ISD::BUILTIN_OP_END) {
Action = TargetLowering::Legal;
return 0;
}
+ case Intrinsic::debugtrap:
case Intrinsic::trap: {
StringRef TrapFuncName = TM.Options.getTrapFunctionName();
if (TrapFuncName.empty()) {
- DAG.setRoot(DAG.getNode(ISD::TRAP, dl,MVT::Other, getRoot()));
+ ISD::NodeType Op = (Intrinsic == Intrinsic::trap) ?
+ ISD::TRAP : ISD::DEBUGTRAP;
+ DAG.setRoot(DAG.getNode(Op, dl,MVT::Other, getRoot()));
return 0;
}
TargetLowering::ArgListTy Args;
DAG.setRoot(Result.second);
return 0;
}
- case Intrinsic::debugtrap: {
- DAG.setRoot(DAG.getNode(ISD::DEBUGTRAP, dl,MVT::Other, getRoot()));
- return 0;
- }
+
case Intrinsic::uadd_with_overflow:
case Intrinsic::sadd_with_overflow:
case Intrinsic::usub_with_overflow:
// Default ISD::TRAP to expand (which turns it into abort).
setOperationAction(ISD::TRAP, MVT::Other, Expand);
+ // On most systems, DEBUGTRAP and TRAP have no difference. The "Expand"
+ // here is to inform DAG Legalizer to replace DEBUGTRAP with TRAP.
+ //
+ setOperationAction(ISD::DEBUGTRAP, MVT::Other, Expand);
+
IsLittleEndian = TD->isLittleEndian();
PointerTy = MVT::getIntegerVT(8*TD->getPointerSize(0));
memset(RegClassForVT, 0,MVT::LAST_VALUETYPE*sizeof(TargetRegisterClass*));
setOperationAction(ISD::ADJUST_TRAMPOLINE, MVT::Other, Custom);
setOperationAction(ISD::TRAP, MVT::Other, Legal);
+ setOperationAction(ISD::DEBUGTRAP, MVT::Other, Legal);
// VASTART needs to be custom lowered to use the VarArgsFrameIndex
setOperationAction(ISD::VASTART , MVT::Other, Custom);
unreachable
}
+define void @t2() nounwind {
+entry:
+; INSTR: t2:
+; INSTR: trap
+
+; FUNC: t2:
+; FUNC: bl __trap
+ call void @llvm.debugtrap()
+ unreachable
+}
+
declare void @llvm.trap() nounwind
+declare void @llvm.debugtrap() nounwind