WebAssemblyFastISel.cpp File Reference

This file defines the WebAssembly-specific support for the FastISel class. More...

#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
#include "Utils/WasmAddressSpaces.h"
#include "Utils/WebAssemblyTypeUtilities.h"
#include "WebAssemblyMachineFunctionInfo.h"
#include "WebAssemblySubtarget.h"
#include "WebAssemblyUtilities.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/FunctionLoweringInfo.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Operator.h"
#include "WebAssemblyGenFastISel.inc"

Go to the source code of this file.

Macros
#define	DEBUG_TYPE   "wasm-fastisel"

Functions
static unsigned	getSExtLoadOpcode (unsigned Opc, bool A64)
static unsigned	getZExtLoadOpcodeFromAnd (MachineInstr *MI, MachineRegisterInfo &MRI, const LoadInst *LI, bool A64)
static unsigned	getFoldedLoadOpcode (MachineInstr *MI, MachineRegisterInfo &MRI, const LoadInst *LI, bool A64)
static unsigned	matchFoldableShift (MachineInstr *MI, const LoadInst *LI, MachineRegisterInfo &MRI, bool A64, MachineInstr *&UserMI)
	Matches a sign-extension pattern (shl + shr_s) to fold it into a signed load.

Detailed Description

This file defines the WebAssembly-specific support for the FastISel class.

Some of the target-specific code is generated by tablegen in the file WebAssemblyGenFastISel.inc, which is #included here.

TODO: kill flags

Definition in file WebAssemblyFastISel.cpp.

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "wasm-fastisel"

Definition at line 42 of file WebAssemblyFastISel.cpp.

Function Documentation

getFoldedLoadOpcode()

unsigned getFoldedLoadOpcode ( MachineInstr * MI, MachineRegisterInfo & MRI, const LoadInst * LI, bool A64 )

static

Definition at line 1355 of file WebAssemblyFastISel.cpp.

References getSExtLoadOpcode(), getZExtLoadOpcodeFromAnd(), and MI.

getSExtLoadOpcode()

unsigned getSExtLoadOpcode ( unsigned Opc, bool A64 )

static

Definition at line 1287 of file WebAssemblyFastISel.cpp.

References Opc.

Referenced by getFoldedLoadOpcode().

getZExtLoadOpcodeFromAnd()

unsigned getZExtLoadOpcodeFromAnd ( MachineInstr * MI, MachineRegisterInfo & MRI, const LoadInst * LI, bool A64 )

static

Definition at line 1312 of file WebAssemblyFastISel.cpp.

References DefMI, llvm::Type::getPrimitiveSizeInBits(), llvm::Value::getType(), llvm::MachineRegisterInfo::getUniqueVRegDef(), I, llvm::maskTrailingOnes(), MI, and Reg.

Referenced by getFoldedLoadOpcode().

matchFoldableShift()

unsigned matchFoldableShift ( MachineInstr * MI, const LoadInst * LI, MachineRegisterInfo & MRI, bool A64, MachineInstr *& UserMI )

static

Matches a sign-extension pattern (shl + shr_s) to fold it into a signed load.

FastISel assumes that 'sext' from i8 or i16 will first be lowered to a 32-bit zero-extending load (i32.load8_u / i32.load16_u) followed by 32-bit shifts, even when extending to i64. Therefore, this function only matches 32-bit shifts (SHL_I32 / SHR_S_I32) and specifically checks if both shift amounts are identical, compile-time constants that match the exact extension size (32 - LoadBitWidth).

Definition at line 1380 of file WebAssemblyFastISel.cpp.

References llvm::Type::getIntegerBitWidth(), llvm::MachineInstr::getOpcode(), llvm::MachineInstr::getOperand(), llvm::MachineOperand::getReg(), llvm::Value::getType(), llvm::MachineRegisterInfo::getUniqueVRegDef(), llvm::MachineRegisterInfo::hasOneNonDBGUse(), llvm::Type::isIntegerTy(), MI, Opc, and llvm::MachineRegisterInfo::use_instr_nodbg_begin().