Next step in Mips16 prologue/epilogue cleanup.

Save S2(reg 18) only when we are calling floating point stubs that
have a return value of float or complex. Some more work to make this
better but this is the first step.

llvm-svn: 196921
This commit is contained in:
Reed Kotler 2013-12-10 14:29:38 +00:00
parent 57057960b0
commit 1f7ad447b7
9 changed files with 159 additions and 27 deletions

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@ -15,6 +15,7 @@
#include "MCTargetDesc/MipsBaseInfo.h"
#include "Mips16InstrInfo.h"
#include "MipsInstrInfo.h"
#include "MipsRegisterInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
@ -56,17 +57,31 @@ void Mips16FrameLowering::emitPrologue(MachineFunction &MF) const {
MCSymbol *CSLabel = MMI.getContext().CreateTempSymbol();
BuildMI(MBB, MBBI, dl,
TII.get(TargetOpcode::PROLOG_LABEL)).addSym(CSLabel);
unsigned S2 = MRI->getDwarfRegNum(Mips::S2, true);
MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel, S2, -8));
const MipsRegisterInfo &RI = TII.getRegisterInfo();
const BitVector Reserved = RI.getReservedRegs(MF);
bool SaveS2 = Reserved[Mips::S2];
int Offset=-4;
unsigned RA = MRI->getDwarfRegNum(Mips::RA, true);
MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel, RA, Offset));
Offset -= 4;
if (SaveS2) {
unsigned S2 = MRI->getDwarfRegNum(Mips::S2, true);
MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel, S2, Offset));
Offset -= 4;
}
unsigned S1 = MRI->getDwarfRegNum(Mips::S1, true);
MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel, S1, -12));
MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel, S1, Offset));
Offset -= 4;
unsigned S0 = MRI->getDwarfRegNum(Mips::S0, true);
MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel, S0, -16));
MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel, S0, Offset));
unsigned RA = MRI->getDwarfRegNum(Mips::RA, true);
MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel, RA, -4));
if (hasFP(MF))
BuildMI(MBB, MBBI, dl, TII.get(Mips::MoveR3216), Mips::S0)

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@ -400,13 +400,19 @@ static bool fixupFPReturnAndCall
Value *F = (M->getOrInsertFunction(Name, A, MyVoid, T, NULL));
CallInst::Create(F, Params, "", &Inst );
} else if (const CallInst *CI = dyn_cast<CallInst>(I)) {
Function *F_ = CI->getCalledFunction();
if (F_ && !isIntrinsicInline(F_)) {
// pic mode calls are handled by already defined
// helper functions
if (Subtarget.getRelocationModel() != Reloc::PIC_ ) {
Function *F_ = CI->getCalledFunction();
if (F_ && !isIntrinsicInline(F_) && needsFPHelperFromSig(*F_)) {
assureFPCallStub(*F_, M, Subtarget);
if (needsFPReturnHelper(*F_)) {
Modified=true;
F.addFnAttr("saveS2");
}
if (Subtarget.getRelocationModel() != Reloc::PIC_ ) {
if (needsFPHelperFromSig(*F_)) {
assureFPCallStub(*F_, M, Subtarget);
Modified=true;
}
}
}
}

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@ -173,22 +173,29 @@ void Mips16InstrInfo::makeFrame(unsigned SP, int64_t FrameSize,
MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
DebugLoc DL = I != MBB.end() ? I->getDebugLoc() : DebugLoc();
const BitVector Reserved = RI.getReservedRegs(*MBB.getParent());
bool SaveS2 = Reserved[Mips::S2];
MachineInstrBuilder MIB;
if (isUInt<11>(FrameSize))
BuildMI(MBB, I, DL, get(Mips::SaveX16)).addReg(Mips::RA).
MIB = BuildMI(
MBB, I, DL, get(Mips::SaveX16)).addReg(Mips::RA).
addReg(Mips::S0).
addReg(Mips::S1).addReg(Mips::S2).addImm(FrameSize);
addReg(Mips::S1).addImm(FrameSize);
else {
int Base = 2040; // should create template function like isUInt that
// returns largest possible n bit unsigned integer
int64_t Remainder = FrameSize - Base;
BuildMI(MBB, I, DL, get(Mips::SaveX16)).addReg(Mips::RA).
MIB = BuildMI(
MBB, I, DL, get(Mips::SaveX16)).addReg(Mips::RA).
addReg(Mips::S0).
addReg(Mips::S1).addReg(Mips::S2).addImm(Base);
addReg(Mips::S1).addImm(Base);
if (isInt<16>(-Remainder))
BuildAddiuSpImm(MBB, I, -Remainder);
else
adjustStackPtrBig(SP, -Remainder, MBB, I, Mips::V0, Mips::V1);
}
if (SaveS2)
MIB.addReg(Mips::S2);
}
// Adjust SP by FrameSize bytes. Restore RA, S0, S1
@ -196,12 +203,16 @@ void Mips16InstrInfo::restoreFrame(unsigned SP, int64_t FrameSize,
MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
DebugLoc DL = I != MBB.end() ? I->getDebugLoc() : DebugLoc();
const BitVector Reserved = RI.getReservedRegs(*MBB.getParent());
bool SaveS2 = Reserved[Mips::S2];
MachineInstrBuilder MIB;
if (isUInt<11>(FrameSize))
BuildMI(MBB, I, DL, get(Mips::RestoreX16)).
MIB = BuildMI(
MBB, I, DL, get(Mips::RestoreX16)).
addReg(Mips::RA, RegState::Define).
addReg(Mips::S0, RegState::Define).
addReg(Mips::S1, RegState::Define).
addReg(Mips::S2, RegState::Define).addImm(FrameSize);
addImm(FrameSize);
else {
int Base = 2040; // should create template function like isUInt that
// returns largest possible n bit unsigned integer
@ -210,12 +221,15 @@ void Mips16InstrInfo::restoreFrame(unsigned SP, int64_t FrameSize,
BuildAddiuSpImm(MBB, I, Remainder);
else
adjustStackPtrBig(SP, Remainder, MBB, I, Mips::A0, Mips::A1);
BuildMI(MBB, I, DL, get(Mips::RestoreX16)).
MIB = BuildMI(
MBB, I, DL, get(Mips::RestoreX16)).
addReg(Mips::RA, RegState::Define).
addReg(Mips::S0, RegState::Define).
addReg(Mips::S1, RegState::Define).
addReg(Mips::S2, RegState::Define).addImm(Base);
addImm(Base);
}
if (SaveS2)
MIB.addReg(Mips::S2, RegState::Define);
}
// Adjust SP by Amount bytes where bytes can be up to 32bit number.

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@ -27,6 +27,7 @@
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/DebugInfo.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
@ -183,6 +184,8 @@ getReservedRegs(const MachineFunction &MF) const {
Reserved.set(Mips::RA_64);
Reserved.set(Mips::T0);
Reserved.set(Mips::T1);
if (MF.getFunction()->hasFnAttribute("saveS2"))
Reserved.set(Mips::S2);
}
// Reserve GP if small section is used.

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@ -25,7 +25,7 @@ entry:
call void @p(i32* %arrayidx1)
ret void
}
; 16: save $ra, $16, $17, $18, 2040
; 16: save $ra, $16, $17, 2040
; 16: addiu $sp, -56 # 16 bit inst
; 16: addiu $sp, 56 # 16 bit inst
; 16: restore $ra, $16, $17, $18, 2040
; 16: restore $ra, $16, $17, 2040

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@ -20,7 +20,7 @@ entry:
define void @test() nounwind {
entry:
; 16: .frame $sp,24,$ra
; 16: save $ra, $16, $17, $18, 24
; 16: save $ra, $16, $17, 24
; 16: move $16, $sp
; 16: move ${{[0-9]+}}, $sp
; 16: subu $[[REGISTER:[0-9]+]], ${{[0-9]+}}, ${{[0-9]+}}

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@ -6,12 +6,11 @@
define i32 @main() {
; 16-LABEL: main:
; 16: .cfi_startproc
; 16: save $ra, $16, $17, $18, 40
; 16: save $ra, $16, $17, 40
; 16: .cfi_def_cfa_offset 40
; 16: .cfi_offset 18, -8
; 16: .cfi_offset 17, -12
; 16: .cfi_offset 16, -16
; 16: .cfi_offset 31, -4
; 16: .cfi_offset 17, -8
; 16: .cfi_offset 16, -12
; 16: .cfi_endproc
entry:
%retval = alloca i32, align 4

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@ -25,7 +25,7 @@ entry:
; SR32: .set noreorder
; SR32: .set nomacro
; SR32: .set noat
; SR: save $ra, $16, $17, $18, [[FS:[0-9]+]]
; SR: save $ra, $16, $17, [[FS:[0-9]+]]
; PE: .ent main
; PE: .align 2
; PE-NEXT: li $[[T1:[0-9]+]], %hi(_gp_disp)
@ -37,7 +37,7 @@ entry:
; C2: move $25, ${{[0-9]+}}
; C1: move $gp, ${{[0-9]+}}
; C1: jalrc ${{[0-9]+}}
; SR: restore $ra, $16, $17, $18, [[FS]]
; SR: restore $ra, $16, $17, [[FS]]
; PE: li $2, 0
; PE: jrc $ra

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@ -0,0 +1,95 @@
; RUN: llc -mtriple=mipsel-linux-gnu -march=mipsel -mcpu=mips16 -relocation-model=pic < %s | FileCheck %s -check-prefix=NEG
; RUN: llc -mtriple=mipsel-linux-gnu -march=mipsel -mcpu=mips16 -relocation-model=static < %s | FileCheck %s -check-prefix=NEG
; RUN: llc -mtriple=mipsel-linux-gnu -march=mipsel -mcpu=mips16 -relocation-model=pic < %s | FileCheck %s
; RUN: llc -mtriple=mipsel-linux-gnu -march=mipsel -mcpu=mips16 -relocation-model=static < %s | FileCheck %s
@xi = common global i32 0, align 4
@x = common global float 0.000000e+00, align 4
@xd = common global double 0.000000e+00, align 8
; Function Attrs: nounwind
define void @it() #0 {
entry:
%call = call i32 @i(i32 1)
store i32 %call, i32* @xi, align 4
ret void
; CHECK: .ent it
; NEG: .ent it
; CHECK: save $ra, $16, $17, [[FS:[0-9]+]]
; NEG-NOT: save $ra, $16, $17, [[FS:[0-9]+]], $18
; CHECK: restore $ra, $16, $17, [[FS]]
; NEG-NOT: restore $ra, $16, $17, [[FS:[0-9]+]], $18
; CHECK: .end it
; NEG: .end it
}
declare i32 @i(i32) #1
; Function Attrs: nounwind
define void @ft() #0 {
entry:
%call = call float @f()
store float %call, float* @x, align 4
ret void
; CHECK: .ent ft
; CHECK: save $ra, $16, $17, [[FS:[0-9]+]], $18
; CHECK: restore $ra, $16, $17, [[FS]], $18
; CHECK: .end ft
}
declare float @f() #1
; Function Attrs: nounwind
define void @dt() #0 {
entry:
%call = call double @d()
store double %call, double* @xd, align 8
ret void
; CHECK: .ent dt
; CHECK: save $ra, $16, $17, [[FS:[0-9]+]], $18
; CHECK: restore $ra, $16, $17, [[FS]], $18
; CHECK: .end dt
}
declare double @d() #1
; Function Attrs: nounwind
define void @fft() #0 {
entry:
%0 = load float* @x, align 4
%call = call float @ff(float %0)
store float %call, float* @x, align 4
ret void
; CHECK: .ent fft
; CHECK: save $ra, $16, $17, [[FS:[0-9]+]], $18
; CHECK: restore $ra, $16, $17, [[FS]], $18
; CHECK: .end fft
}
declare float @ff(float) #1
; Function Attrs: nounwind
define void @vft() #0 {
entry:
%0 = load float* @x, align 4
call void @vf(float %0)
ret void
; CHECK: .ent vft
; NEG: .ent vft
; CHECK: save $ra, $16, $17, [[FS:[0-9]+]]
; NEG-NOT: save $ra, $16, $17, [[FS:[0-9]+]], $18
; CHECK: restore $ra, $16, $17, [[FS]]
; NEG-NOT: restore $ra, $16, $17, [[FS:[0-9]+]], $18
; CHECK: .end vft
; NEG: .end vft
}
declare void @vf(float) #1
attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }