diff options
| author | Evan Cheng <evan.cheng@apple.com> | 2012-02-28 06:42:03 +0000 |
|---|---|---|
| committer | Evan Cheng <evan.cheng@apple.com> | 2012-02-28 06:42:03 +0000 |
| commit | 87c7b09d8d7e7f04b720d298a7194c4473a8c524 (patch) | |
| tree | bbb0ebbd77e5a544fbe06f60bbb05802170d23d1 /llvm/lib/Target/ARM/ARMISelLowering.h | |
| parent | ccd651cac84b0620192f0ca404a841d52ad3a387 (diff) | |
| download | bcm5719-llvm-87c7b09d8d7e7f04b720d298a7194c4473a8c524.tar.gz bcm5719-llvm-87c7b09d8d7e7f04b720d298a7194c4473a8c524.zip | |
Some ARM implementaions, e.g. A-series, does return stack prediction. That is,
the processor keeps a return addresses stack (RAS) which stores the address
and the instruction execution state of the instruction after a function-call
type branch instruction.
Calling a "noreturn" function with normal call instructions (e.g. bl) can
corrupt RAS and causes 100% return misprediction so LLVM should use a
unconditional branch instead. i.e.
mov lr, pc
b _foo
The "mov lr, pc" is issued in order to get proper backtrace.
rdar://8979299
llvm-svn: 151623
Diffstat (limited to 'llvm/lib/Target/ARM/ARMISelLowering.h')
| -rw-r--r-- | llvm/lib/Target/ARM/ARMISelLowering.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/llvm/lib/Target/ARM/ARMISelLowering.h b/llvm/lib/Target/ARM/ARMISelLowering.h index a72a476e962..7f122935260 100644 --- a/llvm/lib/Target/ARM/ARMISelLowering.h +++ b/llvm/lib/Target/ARM/ARMISelLowering.h @@ -462,7 +462,7 @@ namespace llvm { virtual SDValue LowerCall(SDValue Chain, SDValue Callee, CallingConv::ID CallConv, bool isVarArg, - bool &isTailCall, + bool doesNotRet, bool &isTailCall, const SmallVectorImpl<ISD::OutputArg> &Outs, const SmallVectorImpl<SDValue> &OutVals, const SmallVectorImpl<ISD::InputArg> &Ins, |
