Now that we have the ReturnsTwice function attribute, this method is

obsolete. Check the attribute instead.
<rdar://problem/8031714>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142212 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bill Wendling 2011-10-17 18:22:52 +00:00
parent f1fddcd9e0
commit 728662f9e8
5 changed files with 7 additions and 52 deletions

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@ -425,10 +425,6 @@ public:
/// ///
bool hasAddressTaken(const User** = 0) const; bool hasAddressTaken(const User** = 0) const;
/// callsFunctionThatReturnsTwice - Return true if the function has a call to
/// setjmp or other function that gcc recognizes as "returning twice".
bool callsFunctionThatReturnsTwice() const;
private: private:
// Shadow Value::setValueSubclassData with a private forwarding method so that // Shadow Value::setValueSubclassData with a private forwarding method so that
// subclasses cannot accidentally use it. // subclasses cannot accidentally use it.

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@ -225,12 +225,11 @@ unsigned CodeMetrics::CountCodeReductionForAlloca(Value *V) {
/// analyzeFunction - Fill in the current structure with information gleaned /// analyzeFunction - Fill in the current structure with information gleaned
/// from the specified function. /// from the specified function.
void CodeMetrics::analyzeFunction(Function *F, const TargetData *TD) { void CodeMetrics::analyzeFunction(Function *F, const TargetData *TD) {
// If this function contains a call to setjmp or _setjmp, never inline // If this function contains a call that "returns twice" (e.g., setjmp or
// it. This is a hack because we depend on the user marking their local // _setjmp), never inline it. This is a hack because we depend on the user
// variables as volatile if they are live across a setjmp call, and they // marking their local variables as volatile if they are live across a setjmp
// probably won't do this in callers. // call, and they probably won't do this in callers.
if (F->callsFunctionThatReturnsTwice()) callsSetJmp = F->hasFnAttr(Attribute::ReturnsTwice);
callsSetJmp = true;
// Look at the size of the callee. // Look at the size of the callee.
for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB) for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)

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@ -374,7 +374,7 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
} }
// Determine if there is a call to setjmp in the machine function. // Determine if there is a call to setjmp in the machine function.
MF->setCallsSetJmp(Fn.callsFunctionThatReturnsTwice()); MF->setCallsSetJmp(Fn.hasFnAttr(Attribute::ReturnsTwice));
// Replace forward-declared registers with the registers containing // Replace forward-declared registers with the registers containing
// the desired value. // the desired value.

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@ -213,7 +213,7 @@ bool TailCallElim::runOnFunction(Function &F) {
// Finally, if this function contains no non-escaping allocas, or calls // Finally, if this function contains no non-escaping allocas, or calls
// setjmp, mark all calls in the function as eligible for tail calls // setjmp, mark all calls in the function as eligible for tail calls
//(there is no stack memory for them to access). //(there is no stack memory for them to access).
if (!FunctionContainsEscapingAllocas && !F.callsFunctionThatReturnsTwice()) if (!FunctionContainsEscapingAllocas && !F.hasFnAttr(Attribute::ReturnsTwice))
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
if (CallInst *CI = dyn_cast<CallInst>(I)) { if (CallInst *CI = dyn_cast<CallInst>(I)) {

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@ -411,44 +411,4 @@ bool Function::hasAddressTaken(const User* *PutOffender) const {
return false; return false;
} }
/// callsFunctionThatReturnsTwice - Return true if the function has a call to
/// setjmp or other function that gcc recognizes as "returning twice".
///
/// FIXME: Remove after <rdar://problem/8031714> is fixed.
/// FIXME: Is the above FIXME valid?
bool Function::callsFunctionThatReturnsTwice() const {
static const char *const ReturnsTwiceFns[] = {
"_setjmp",
"setjmp",
"sigsetjmp",
"setjmp_syscall",
"savectx",
"qsetjmp",
"vfork",
"getcontext"
};
for (const_inst_iterator I = inst_begin(this), E = inst_end(this); I != E;
++I) {
const CallInst* callInst = dyn_cast<CallInst>(&*I);
if (!callInst)
continue;
if (callInst->canReturnTwice())
return true;
// check for known function names.
// FIXME: move this to clang.
Function *F = callInst->getCalledFunction();
if (!F)
continue;
StringRef Name = F->getName();
for (unsigned J = 0, e = array_lengthof(ReturnsTwiceFns); J != e; ++J) {
if (Name == ReturnsTwiceFns[J])
return true;
}
}
return false;
}
// vim: sw=2 ai // vim: sw=2 ai