diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Target/ARM/ARMISelLowering.cpp | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp index 97a5f9d..ceb6806 100644 --- a/lib/Target/ARM/ARMISelLowering.cpp +++ b/lib/Target/ARM/ARMISelLowering.cpp @@ -1408,29 +1408,26 @@ ARMTargetLowering::IsEligibleForTailCallOptimization(SDValue Callee, if (isCalleeStructRet || isCallerStructRet) return false; - // FIXME: Completely disable sibcal for Thumb1 since Thumb1RegisterInfo:: + // FIXME: Completely disable sibcall for Thumb1 since Thumb1RegisterInfo:: // emitEpilogue is not ready for them. if (Subtarget->isThumb1Only()) return false; + // For the moment, we can only do this to functions defined in this + // compilation, or to indirect calls. A Thumb B to an ARM function, + // or vice versa, is not easily fixed up in the linker unlike BL. + // (We could do this by loading the address of the callee into a register; + // that is an extra instruction over the direct call and burns a register + // as well, so is not likely to be a win.) if (isa<ExternalSymbolSDNode>(Callee)) return false; if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) { - if (Subtarget->isThumb1Only()) + const GlobalValue *GV = G->getGlobal(); + if (GV->isDeclaration() || GV->isWeakForLinker()) return false; - - // On Thumb, for the moment, we can only do this to functions defined in this - // compilation, or to indirect calls. A Thumb B to an ARM function is not - // easily fixed up in the linker, unlike BL. - if (Subtarget->isThumb()) { - const GlobalValue *GV = G->getGlobal(); - if (GV->isDeclaration() || GV->isWeakForLinker()) - return false; - } } - // If the calling conventions do not match, then we'd better make sure the // results are returned in the same way as what the caller expects. if (!CCMatch) { |