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//===-- X86ISelLowering.h - X86 DAG Lowering Interface ----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that X86 uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//
#include "X86.h"
#include "X86ISelLowering.h"
#include "X86TargetMachine.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
#include "llvm/Function.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SSARegMap.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
// FIXME: temporary.
#include "llvm/Support/CommandLine.h"
static cl::opt<bool> EnableFastCC("enable-x86-fastcc", cl::Hidden,
cl::desc("Enable fastcc on X86"));
X86TargetLowering::X86TargetLowering(TargetMachine &TM)
: TargetLowering(TM) {
Subtarget = &TM.getSubtarget<X86Subtarget>();
X86ScalarSSE = Subtarget->hasSSE2();
// Set up the TargetLowering object.
// X86 is weird, it always uses i8 for shift amounts and setcc results.
setShiftAmountType(MVT::i8);
setSetCCResultType(MVT::i8);
setSetCCResultContents(ZeroOrOneSetCCResult);
setSchedulingPreference(SchedulingForRegPressure);
setShiftAmountFlavor(Mask); // shl X, 32 == shl X, 0
setStackPointerRegisterToSaveRestore(X86::ESP);
// Set up the register classes.
addRegisterClass(MVT::i8, X86::R8RegisterClass);
addRegisterClass(MVT::i16, X86::R16RegisterClass);
addRegisterClass(MVT::i32, X86::R32RegisterClass);
// Promote all UINT_TO_FP to larger SINT_TO_FP's, as X86 doesn't have this
// operation.
setOperationAction(ISD::UINT_TO_FP , MVT::i1 , Promote);
setOperationAction(ISD::UINT_TO_FP , MVT::i8 , Promote);
setOperationAction(ISD::UINT_TO_FP , MVT::i16 , Promote);
if (X86ScalarSSE)
// No SSE i64 SINT_TO_FP, so expand i32 UINT_TO_FP instead.
setOperationAction(ISD::UINT_TO_FP , MVT::i32 , Expand);
else
setOperationAction(ISD::UINT_TO_FP , MVT::i32 , Promote);
// Promote i1/i8 SINT_TO_FP to larger SINT_TO_FP's, as X86 doesn't have
// this operation.
setOperationAction(ISD::SINT_TO_FP , MVT::i1 , Promote);
setOperationAction(ISD::SINT_TO_FP , MVT::i8 , Promote);
// SSE has no i16 to fp conversion, only i32
if (X86ScalarSSE)
setOperationAction(ISD::SINT_TO_FP , MVT::i16 , Promote);
else {
setOperationAction(ISD::SINT_TO_FP , MVT::i16 , Custom);
setOperationAction(ISD::SINT_TO_FP , MVT::i32 , Custom);
}
// We can handle SINT_TO_FP and FP_TO_SINT from/to i64 even though i64
// isn't legal.
setOperationAction(ISD::SINT_TO_FP , MVT::i64 , Custom);
setOperationAction(ISD::FP_TO_SINT , MVT::i64 , Custom);
// Promote i1/i8 FP_TO_SINT to larger FP_TO_SINTS's, as X86 doesn't have
// this operation.
setOperationAction(ISD::FP_TO_SINT , MVT::i1 , Promote);
setOperationAction(ISD::FP_TO_SINT , MVT::i8 , Promote);
if (X86ScalarSSE) {
setOperationAction(ISD::FP_TO_SINT , MVT::i16 , Promote);
} else {
setOperationAction(ISD::FP_TO_SINT , MVT::i16 , Custom);
setOperationAction(ISD::FP_TO_SINT , MVT::i32 , Custom);
}
// Handle FP_TO_UINT by promoting the destination to a larger signed
// conversion.
setOperationAction(ISD::FP_TO_UINT , MVT::i1 , Promote);
setOperationAction(ISD::FP_TO_UINT , MVT::i8 , Promote);
setOperationAction(ISD::FP_TO_UINT , MVT::i16 , Promote);
if (X86ScalarSSE && !Subtarget->hasSSE3())
// Expand FP_TO_UINT into a select.
// FIXME: We would like to use a Custom expander here eventually to do
// the optimal thing for SSE vs. the default expansion in the legalizer.
setOperationAction(ISD::FP_TO_UINT , MVT::i32 , Expand);
else
// With SSE3 we can use fisttpll to convert to a signed i64.
setOperationAction(ISD::FP_TO_UINT , MVT::i32 , Promote);
setOperationAction(ISD::BIT_CONVERT , MVT::f32 , Expand);
setOperationAction(ISD::BIT_CONVERT , MVT::i32 , Expand);
setOperationAction(ISD::BRCONDTWOWAY , MVT::Other, Expand);
setOperationAction(ISD::BRTWOWAY_CC , MVT::Other, Expand);
setOperationAction(ISD::BR_CC , MVT::Other, Expand);
setOperationAction(ISD::SELECT_CC , MVT::Other, Expand);
setOperationAction(ISD::MEMMOVE , MVT::Other, Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16 , Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8 , Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1 , Expand);
setOperationAction(ISD::FP_ROUND_INREG , MVT::f32 , Expand);
setOperationAction(ISD::SEXTLOAD , MVT::i1 , Expand);
setOperationAction(ISD::FREM , MVT::f64 , Expand);
setOperationAction(ISD::CTPOP , MVT::i8 , Expand);
setOperationAction(ISD::CTTZ , MVT::i8 , Expand);
setOperationAction(ISD::CTLZ , MVT::i8 , Expand);
setOperationAction(ISD::CTPOP , MVT::i16 , Expand);
setOperationAction(ISD::CTTZ , MVT::i16 , Expand);
setOperationAction(ISD::CTLZ , MVT::i16 , Expand);
setOperationAction(ISD::CTPOP , MVT::i32 , Expand);
setOperationAction(ISD::CTTZ , MVT::i32 , Expand);
setOperationAction(ISD::CTLZ , MVT::i32 , Expand);
setOperationAction(ISD::READCYCLECOUNTER , MVT::i64 , Custom);
setOperationAction(ISD::READIO , MVT::i1 , Expand);
setOperationAction(ISD::READIO , MVT::i8 , Expand);
setOperationAction(ISD::READIO , MVT::i16 , Expand);
setOperationAction(ISD::READIO , MVT::i32 , Expand);
setOperationAction(ISD::WRITEIO , MVT::i1 , Expand);
setOperationAction(ISD::WRITEIO , MVT::i8 , Expand);
setOperationAction(ISD::WRITEIO , MVT::i16 , Expand);
setOperationAction(ISD::WRITEIO , MVT::i32 , Expand);
// These should be promoted to a larger select which is supported.
setOperationAction(ISD::SELECT , MVT::i1 , Promote);
setOperationAction(ISD::SELECT , MVT::i8 , Promote);
setOperationAction(ISD::SELECT , MVT::i16 , Custom);
setOperationAction(ISD::SELECT , MVT::i32 , Custom);
setOperationAction(ISD::SELECT , MVT::f32 , Custom);
setOperationAction(ISD::SELECT , MVT::f64 , Custom);
setOperationAction(ISD::SETCC , MVT::i8 , Custom);
setOperationAction(ISD::SETCC , MVT::i16 , Custom);
setOperationAction(ISD::SETCC , MVT::i32 , Custom);
setOperationAction(ISD::SETCC , MVT::f32 , Custom);
setOperationAction(ISD::SETCC , MVT::f64 , Custom);
setOperationAction(ISD::ConstantPool , MVT::i32 , Custom);
// 64-bit addm sub, shl, sra, srl (iff 32-bit x86)
setOperationAction(ISD::SHL_PARTS , MVT::i32 , Custom);
setOperationAction(ISD::SRA_PARTS , MVT::i32 , Custom);
setOperationAction(ISD::SRL_PARTS , MVT::i32 , Custom);
// X86 wants to expand memset / memcpy itself.
setOperationAction(ISD::MEMSET , MVT::Other, Custom);
setOperationAction(ISD::MEMCPY , MVT::Other, Custom);
// We don't have line number support yet.
setOperationAction(ISD::LOCATION, MVT::Other, Expand);
setOperationAction(ISD::DEBUG_LOC, MVT::Other, Expand);
setOperationAction(ISD::DEBUG_LABEL, MVT::Other, Expand);
// VASTART needs to be custom lowered to use the VarArgsFrameIndex
setOperationAction(ISD::VASTART , MVT::Other, Custom);
// Use the default implementation.
setOperationAction(ISD::VAARG , MVT::Other, Expand);
setOperationAction(ISD::VACOPY , MVT::Other, Expand);
setOperationAction(ISD::VAEND , MVT::Other, Expand);
setOperationAction(ISD::STACKSAVE, MVT::Other, Expand);
setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand);
setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32 , Expand);
if (X86ScalarSSE) {
// Set up the FP register classes.
addRegisterClass(MVT::f32, X86::FR32RegisterClass);
addRegisterClass(MVT::f64, X86::FR64RegisterClass);
// SSE has no load+extend ops
setOperationAction(ISD::EXTLOAD, MVT::f32, Expand);
setOperationAction(ISD::ZEXTLOAD, MVT::f32, Expand);
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