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-rw-r--r--lib/Target/Mips/Mips16HardFloat.cpp277
1 files changed, 277 insertions, 0 deletions
diff --git a/lib/Target/Mips/Mips16HardFloat.cpp b/lib/Target/Mips/Mips16HardFloat.cpp
index 4d1e61bb99..cc7324f26e 100644
--- a/lib/Target/Mips/Mips16HardFloat.cpp
+++ b/lib/Target/Mips/Mips16HardFloat.cpp
@@ -18,6 +18,36 @@
#include "llvm/Support/raw_ostream.h"
#include <string>
+static void inlineAsmOut
+ (LLVMContext &C, StringRef AsmString, BasicBlock *BB ) {
+ std::vector<llvm::Type *> AsmArgTypes;
+ std::vector<llvm::Value*> AsmArgs;
+ llvm::FunctionType *AsmFTy =
+ llvm::FunctionType::get(Type::getVoidTy(C),
+ AsmArgTypes, false);
+ llvm::InlineAsm *IA =
+ llvm::InlineAsm::get(AsmFTy, AsmString, "", true,
+ /* IsAlignStack */ false,
+ llvm::InlineAsm::AD_ATT);
+ CallInst::Create(IA, AsmArgs, "", BB);
+}
+
+namespace {
+
+class InlineAsmHelper {
+ LLVMContext &C;
+ BasicBlock *BB;
+public:
+ InlineAsmHelper(LLVMContext &C_, BasicBlock *BB_) :
+ C(C_), BB(BB_) {
+ }
+
+ void Out(StringRef AsmString) {
+ inlineAsmOut(C, AsmString, BB);
+ }
+
+};
+}
//
// Return types that matter for hard float are:
// float, double, complex float, and complex double
@@ -52,6 +82,243 @@ static FPReturnVariant whichFPReturnVariant(Type *T) {
}
//
+// Parameter type that matter are float, (float, float), (float, double),
+// double, (double, double), (double, float)
+//
+enum FPParamVariant {
+ FSig, FFSig, FDSig,
+ DSig, DDSig, DFSig, NoSig
+};
+
+// which floating point parameter signature variant we are dealing with
+//
+typedef Type::TypeID TypeID;
+const Type::TypeID FloatTyID = Type::FloatTyID;
+const Type::TypeID DoubleTyID = Type::DoubleTyID;
+
+static FPParamVariant whichFPParamVariantNeeded(Function &F) {
+ switch (F.arg_size()) {
+ case 0:
+ return NoSig;
+ case 1:{
+ TypeID ArgTypeID = F.getFunctionType()->getParamType(0)->getTypeID();
+ switch (ArgTypeID) {
+ case FloatTyID:
+ return FSig;
+ case DoubleTyID:
+ return DSig;
+ default:
+ return NoSig;
+ }
+ }
+ default: {
+ TypeID ArgTypeID0 = F.getFunctionType()->getParamType(0)->getTypeID();
+ TypeID ArgTypeID1 = F.getFunctionType()->getParamType(1)->getTypeID();
+ switch(ArgTypeID0) {
+ case FloatTyID: {
+ switch (ArgTypeID1) {
+ case FloatTyID:
+ return FFSig;
+ case DoubleTyID:
+ return FDSig;
+ default:
+ return FSig;
+ }
+ }
+ case DoubleTyID: {
+ switch (ArgTypeID1) {
+ case FloatTyID:
+ return DFSig;
+ case DoubleTyID:
+ return DDSig;
+ default:
+ return DSig;
+ }
+ }
+ default:
+ return NoSig;
+ }
+ }
+ }
+ llvm_unreachable("can't get here");
+}
+
+// Figure out if we need float point based on the function parameters.
+// We need to move variables in and/or out of floating point
+// registers because of the ABI
+//
+static bool needsFPStubFromParams(Function &F) {
+ if (F.arg_size() >=1) {
+ Type *ArgType = F.getFunctionType()->getParamType(0);
+ switch (ArgType->getTypeID()) {
+ case Type::FloatTyID:
+ case Type::DoubleTyID:
+ return true;
+ default:
+ break;
+ }
+ }
+ return false;
+}
+
+static bool needsFPReturnHelper(Function &F) {
+ Type* RetType = F.getReturnType();
+ return whichFPReturnVariant(RetType) != NoFPRet;
+}
+
+static bool needsFPHelperFromSig(Function &F) {
+ return needsFPStubFromParams(F) || needsFPReturnHelper(F);
+}
+
+//
+// We swap between FP and Integer registers to allow Mips16 and Mips32 to
+// interoperate
+//
+
+static void swapFPIntParams
+ (FPParamVariant PV, Module *M, InlineAsmHelper &IAH,
+ bool LE, bool ToFP) {
+ //LLVMContext &Context = M->getContext();
+ std::string MI = ToFP? "mtc1 ": "mfc1 ";
+ switch (PV) {
+ case FSig:
+ IAH.Out(MI + "$$4,$$f12");
+ break;
+ case FFSig:
+ IAH.Out(MI +"$$4,$$f12");
+ IAH.Out(MI + "$$5,$$f14");
+ break;
+ case FDSig:
+ IAH.Out(MI + "$$4,$$f12");
+ if (LE) {
+ IAH.Out(MI + "$$6,$$f14");
+ IAH.Out(MI + "$$7,$$f15");
+ } else {
+ IAH.Out(MI + "$$7,$$f14");
+ IAH.Out(MI + "$$6,$$f15");
+ }
+ break;
+ case DSig:
+ if (LE) {
+ IAH.Out(MI + "$$4,$$f12");
+ IAH.Out(MI + "$$5,$$f13");
+ } else {
+ IAH.Out(MI + "$$5,$$f12");
+ IAH.Out(MI + "$$4,$$f13");
+ }
+ break;
+ case DDSig:
+ if (LE) {
+ IAH.Out(MI + "$$4,$$f12");
+ IAH.Out(MI + "$$5,$$f13");
+ IAH.Out(MI + "$$6,$$f14");
+ IAH.Out(MI + "$$7,$$f15");
+ } else {
+ IAH.Out(MI + "$$5,$$f12");
+ IAH.Out(MI + "$$4,$$f13");
+ IAH.Out(MI + "$$7,$$f14");
+ IAH.Out(MI + "$$6,$$f15");
+ }
+ break;
+ case DFSig:
+ if (LE) {
+ IAH.Out(MI + "$$4,$$f12");
+ IAH.Out(MI + "$$5,$$f13");
+ } else {
+ IAH.Out(MI + "$$5,$$f12");
+ IAH.Out(MI + "$$4,$$f13");
+ }
+ IAH.Out(MI + "$$6,$$f14");
+ break;
+ case NoSig:
+ return;
+ }
+}
+//
+// Make sure that we know we already need a stub for this function.
+// Having called needsFPHelperFromSig
+//
+static void assureFPCallStub(Function &F, Module *M,
+ const MipsSubtarget &Subtarget){
+ // for now we only need them for static relocation
+ if (Subtarget.getRelocationModel() == Reloc::PIC_)
+ return;
+ LLVMContext &Context = M->getContext();
+ bool LE = Subtarget.isLittle();
+ std::string Name = F.getName();
+ std::string SectionName = ".mips16.call.fp." + Name;
+ std::string StubName = "__call_stub_" + Name;
+ //
+ // see if we already have the stub
+ //
+ Function *FStub = M->getFunction(StubName);
+ if (FStub && !FStub->isDeclaration()) return;
+ FStub = Function::Create(F.getFunctionType(),
+ Function::InternalLinkage, StubName, M);
+ FStub->addFnAttr("mips16_fp_stub");
+ FStub->addFnAttr(llvm::Attribute::Naked);
+ FStub->addFnAttr(llvm::Attribute::NoUnwind);
+ FStub->addFnAttr("nomips16");
+ FStub->setSection(SectionName);
+ BasicBlock *BB = BasicBlock::Create(Context, "entry", FStub);
+ InlineAsmHelper IAH(Context, BB);
+ FPReturnVariant RV = whichFPReturnVariant(FStub->getReturnType());
+ FPParamVariant PV = whichFPParamVariantNeeded(F);
+ swapFPIntParams(PV, M, IAH, LE, true);
+ if (RV != NoFPRet) {
+ IAH.Out("move $$18, $$31");
+ IAH.Out("jal " + Name);
+ } else {
+ IAH.Out("lui $$25,%hi(" + Name + ")");
+ IAH.Out("addiu $$25,$$25,%lo(" + Name + ")" );
+ }
+ switch (RV) {
+ case FRet:
+ IAH.Out("mfc1 $$2,$$f0");
+ break;
+ case DRet:
+ if (LE) {
+ IAH.Out("mfc1 $$2,$$f0");
+ IAH.Out("mfc1 $$3,$$f1");
+ } else {
+ IAH.Out("mfc1 $$3,$$f0");
+ IAH.Out("mfc1 $$2,$$f1");
+ }
+ break;
+ case CFRet:
+ if (LE) {
+ IAH.Out("mfc1 $$2,$$f0");
+ IAH.Out("mfc1 $$3,$$f2");
+ } else {
+ IAH.Out("mfc1 $$3,$$f0");
+ IAH.Out("mfc1 $$3,$$f2");
+ }
+ break;
+ case CDRet:
+ if (LE) {
+ IAH.Out("mfc1 $$4,$$f2");
+ IAH.Out("mfc1 $$5,$$f3");
+ IAH.Out("mfc1 $$2,$$f0");
+ IAH.Out("mfc1 $$3,$$f1");
+
+ } else {
+ IAH.Out("mfc1 $$5,$$f2");
+ IAH.Out("mfc1 $$4,$$f3");
+ IAH.Out("mfc1 $$3,$$f0");
+ IAH.Out("mfc1 $$2,$$f1");
+ }
+ break;
+ case NoFPRet:
+ break;
+ }
+ if (RV != NoFPRet)
+ IAH.Out("jr $$18");
+ else
+ IAH.Out("jr $$25");
+ new UnreachableInst(Context, BB);
+}
+
+//
// Returns of float, double and complex need to be handled with a helper
// function. The "AndCal" part is coming in a later patch.
//
@@ -96,6 +363,16 @@ static bool fixupFPReturnAndCall
Attribute::ReadNone);
Value *F = (M->getOrInsertFunction(Name, A, MyVoid, T, NULL));
CallInst::Create(F, Params, "", &Inst );
+ } else if (const CallInst *CI = dyn_cast<CallInst>(I)) {
+ // pic mode calls are handled by already defined
+ // helper functions
+ if (Subtarget.getRelocationModel() != Reloc::PIC_ ) {
+ Function *F_ = CI->getCalledFunction();
+ if (F_ && needsFPHelperFromSig(*F_)) {
+ assureFPCallStub(*F_, M, Subtarget);
+ Modified=true;
+ }
+ }
}
}
return Modified;