1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
|
//===-- WebAssemblyRegisterInfo.cpp - WebAssembly Register Information ----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief This file contains the WebAssembly implementation of the
/// TargetRegisterInfo class.
///
//===----------------------------------------------------------------------===//
#include "WebAssemblyRegisterInfo.h"
#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
#include "WebAssemblyFrameLowering.h"
#include "WebAssemblyInstrInfo.h"
#include "WebAssemblyMachineFunctionInfo.h"
#include "WebAssemblySubtarget.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
#define DEBUG_TYPE "wasm-reg-info"
#define GET_REGINFO_TARGET_DESC
#include "WebAssemblyGenRegisterInfo.inc"
WebAssemblyRegisterInfo::WebAssemblyRegisterInfo(const Triple &TT)
: WebAssemblyGenRegisterInfo(0), TT(TT) {}
const MCPhysReg *
WebAssemblyRegisterInfo::getCalleeSavedRegs(const MachineFunction *) const {
static const MCPhysReg CalleeSavedRegs[] = {0};
return CalleeSavedRegs;
}
BitVector
WebAssemblyRegisterInfo::getReservedRegs(const MachineFunction & /*MF*/) const {
BitVector Reserved(getNumRegs());
for (auto Reg : {WebAssembly::SP32, WebAssembly::SP64, WebAssembly::FP32,
WebAssembly::FP64})
Reserved.set(Reg);
return Reserved;
}
void WebAssemblyRegisterInfo::eliminateFrameIndex(
MachineBasicBlock::iterator II, int SPAdj,
unsigned FIOperandNum, RegScavenger * /*RS*/) const {
assert(SPAdj == 0);
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
MachineFunction &MF = *MBB.getParent();
int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
const MachineFrameInfo& MFI = *MF.getFrameInfo();
int64_t FrameOffset = MFI.getStackSize() + MFI.getObjectOffset(FrameIndex);
if (MI.mayLoadOrStore()) {
// If this is a load or store, make it relative to SP and fold the frame
// offset directly in.
assert(FrameOffset >= 0 && MI.getOperand(1).getImm() >= 0);
int64_t Offset = MI.getOperand(1).getImm() + FrameOffset;
if (static_cast<uint64_t>(Offset) > std::numeric_limits<uint32_t>::max()) {
// If this happens the program is invalid, but better to error here than
// generate broken code.
report_fatal_error("Memory offset field overflow");
}
MI.getOperand(1).setImm(Offset);
MI.getOperand(2).ChangeToRegister(WebAssembly::SP32, /*IsDef=*/false);
} else {
// Otherwise create an i32.add SP, offset and make it the operand.
auto &MRI = MF.getRegInfo();
const auto *TII = MF.getSubtarget().getInstrInfo();
unsigned OffsetReg = MRI.createVirtualRegister(&WebAssembly::I32RegClass);
BuildMI(MBB, MI, MI.getDebugLoc(), TII->get(WebAssembly::CONST_I32), OffsetReg)
.addImm(FrameOffset);
BuildMI(MBB, MI, MI.getDebugLoc(), TII->get(WebAssembly::ADD_I32), OffsetReg)
.addReg(WebAssembly::SP32)
.addReg(OffsetReg);
MI.getOperand(FIOperandNum).ChangeToRegister(OffsetReg, /*IsDef=*/false);
}
}
unsigned
WebAssemblyRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
static const unsigned Regs[2][2] = {
/* !isArch64Bit isArch64Bit */
/* !hasFP */ {WebAssembly::SP32, WebAssembly::SP64},
/* hasFP */ {WebAssembly::FP32, WebAssembly::FP64}};
const WebAssemblyFrameLowering *TFI = getFrameLowering(MF);
return Regs[TFI->hasFP(MF)][TT.isArch64Bit()];
}
const TargetRegisterClass *
WebAssemblyRegisterInfo::getPointerRegClass(const MachineFunction &MF,
unsigned Kind) const {
assert(Kind == 0 && "Only one kind of pointer on WebAssembly");
if (MF.getSubtarget<WebAssemblySubtarget>().hasAddr64())
return &WebAssembly::I64RegClass;
return &WebAssembly::I32RegClass;
}
|