//
// Returns of float, double and complex need to be handled with a helper
// function.
//
static bool fixupFPReturnAndCall(Function &F, Module *M,
const MipsTargetMachine &TM) {
bool Modified = false;
LLVMContext &C = M->getContext();
Type *MyVoid = Type::getVoidTy(C);
for (auto &BB: F)
for (auto &I: BB) {
if (const ReturnInst *RI = dyn_cast<ReturnInst>(&I)) {
Value *RVal = RI->getReturnValue();
if (!RVal) continue;
//
// If there is a return value and it needs a helper function,
// figure out which one and add a call before the actual
// return to this helper. The purpose of the helper is to move
// floating point values from their soft float return mapping to
// where they would have been mapped to in floating point registers.
//
Type *T = RVal->getType();
FPReturnVariant RV = whichFPReturnVariant(T);
if (RV == NoFPRet) continue;
static const char *const Helper[NoFPRet] = {
"__mips16_ret_sf", "__mips16_ret_df", "__mips16_ret_sc",
"__mips16_ret_dc"
};
const char *Name = Helper[RV];
AttributeList A;
Value *Params[] = {RVal};
Modified = true;
//
// These helper functions have a different calling ABI so
// this __Mips16RetHelper indicates that so that later
// during call setup, the proper call lowering to the helper
// functions will take place.
//
A = A.addAttribute(C, AttributeList::FunctionIndex,
"__Mips16RetHelper");
A = A.addAttribute(C, AttributeList::FunctionIndex,
Attribute::ReadNone);
A = A.addAttribute(C, AttributeList::FunctionIndex,
Attribute::NoInline);
Value *F = (M->getOrInsertFunction(Name, A, MyVoid, T));
CallInst::Create(F, Params, "", &I);
} else if (const CallInst *CI = dyn_cast<CallInst>(&I)) {
FunctionType *FT = CI->getFunctionType();
Function *F_ = CI->getCalledFunction();
if (needsFPReturnHelper(*FT) &&
!(F_ && isIntrinsicInline(F_))) {
Modified=true;
F.addFnAttr("saveS2");
}
if (F_ && !isIntrinsicInline(F_)) {
// pic mode calls are handled by already defined
// helper functions
if (needsFPReturnHelper(*F_)) {
Modified=true;
F.addFnAttr("saveS2");
}
if (!TM.isPositionIndependent()) {
if (needsFPHelperFromSig(*F_)) {
assureFPCallStub(*F_, M, TM);
Modified=true;
}
}
}
}
}
return Modified;
}
