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-rw-r--r--lib/CodeGen/TwoAddressInstructionPass.cpp84
-rw-r--r--test/CodeGen/X86/cmov.ll8
-rw-r--r--test/CodeGen/X86/jump_sign.ll1
-rw-r--r--test/CodeGen/X86/select.ll2
4 files changed, 12 insertions, 83 deletions
diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index e4c011901e..d71e0673d7 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -55,7 +55,6 @@ STATISTIC(NumCommuted , "Number of instructions commuted to coalesce");
STATISTIC(NumAggrCommuted , "Number of instructions aggressively commuted");
STATISTIC(NumConvertedTo3Addr, "Number of instructions promoted to 3-address");
STATISTIC(Num3AddrSunk, "Number of 3-address instructions sunk");
-STATISTIC(NumReMats, "Number of instructions re-materialized");
STATISTIC(NumDeletes, "Number of dead instructions deleted");
STATISTIC(NumReSchedUps, "Number of instructions re-scheduled up");
STATISTIC(NumReSchedDowns, "Number of instructions re-scheduled down");
@@ -92,10 +91,6 @@ namespace {
unsigned Reg,
MachineBasicBlock::iterator OldPos);
- bool isProfitableToReMat(unsigned Reg, const TargetRegisterClass *RC,
- MachineInstr *MI, MachineInstr *DefMI,
- MachineBasicBlock *MBB, unsigned Loc);
-
bool NoUseAfterLastDef(unsigned Reg, MachineBasicBlock *MBB, unsigned Dist,
unsigned &LastDef);
@@ -301,55 +296,6 @@ bool TwoAddressInstructionPass::Sink3AddrInstruction(MachineBasicBlock *MBB,
return true;
}
-/// isTwoAddrUse - Return true if the specified MI is using the specified
-/// register as a two-address operand.
-static bool isTwoAddrUse(MachineInstr *UseMI, unsigned Reg) {
- const MCInstrDesc &MCID = UseMI->getDesc();
- for (unsigned i = 0, e = MCID.getNumOperands(); i != e; ++i) {
- MachineOperand &MO = UseMI->getOperand(i);
- if (MO.isReg() && MO.getReg() == Reg &&
- (MO.isDef() || UseMI->isRegTiedToDefOperand(i)))
- // Earlier use is a two-address one.
- return true;
- }
- return false;
-}
-
-/// isProfitableToReMat - Return true if the heuristics determines it is likely
-/// to be profitable to re-materialize the definition of Reg rather than copy
-/// the register.
-bool
-TwoAddressInstructionPass::isProfitableToReMat(unsigned Reg,
- const TargetRegisterClass *RC,
- MachineInstr *MI, MachineInstr *DefMI,
- MachineBasicBlock *MBB, unsigned Loc) {
- bool OtherUse = false;
- for (MachineRegisterInfo::use_nodbg_iterator UI = MRI->use_nodbg_begin(Reg),
- UE = MRI->use_nodbg_end(); UI != UE; ++UI) {
- MachineOperand &UseMO = UI.getOperand();
- MachineInstr *UseMI = UseMO.getParent();
- MachineBasicBlock *UseMBB = UseMI->getParent();
- if (UseMBB == MBB) {
- DenseMap<MachineInstr*, unsigned>::iterator DI = DistanceMap.find(UseMI);
- if (DI != DistanceMap.end() && DI->second == Loc)
- continue; // Current use.
- OtherUse = true;
- // There is at least one other use in the MBB that will clobber the
- // register.
- if (isTwoAddrUse(UseMI, Reg))
- return true;
- }
- }
-
- // If other uses in MBB are not two-address uses, then don't remat.
- if (OtherUse)
- return false;
-
- // No other uses in the same block, remat if it's defined in the same
- // block so it does not unnecessarily extend the live range.
- return MBB == DefMI->getParent();
-}
-
/// NoUseAfterLastDef - Return true if there are no intervening uses between the
/// last instruction in the MBB that defines the specified register and the
/// two-address instruction which is being processed. It also returns the last
@@ -538,7 +484,7 @@ regsAreCompatible(unsigned RegA, unsigned RegB, const TargetRegisterInfo *TRI) {
}
-/// isProfitableToReMat - Return true if it's potentially profitable to commute
+/// isProfitableToCommute - Return true if it's potentially profitable to commute
/// the two-address instruction that's being processed.
bool
TwoAddressInstructionPass::isProfitableToCommute(unsigned regA, unsigned regB,
@@ -1518,26 +1464,9 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &MF) {
mi->getOperand(i).getReg() != regA);
#endif
- // Emit a copy or rematerialize the definition.
- bool isCopy = false;
- const TargetRegisterClass *rc = MRI->getRegClass(regB);
- MachineInstr *DefMI = MRI->getUniqueVRegDef(regB);
- // If it's safe and profitable, remat the definition instead of
- // copying it.
- if (DefMI &&
- DefMI->isAsCheapAsAMove() &&
- DefMI->isSafeToReMat(TII, AA, regB) &&
- isProfitableToReMat(regB, rc, mi, DefMI, mbbi, Dist)){
- DEBUG(dbgs() << "2addr: REMATTING : " << *DefMI << "\n");
- unsigned regASubIdx = mi->getOperand(DstIdx).getSubReg();
- TII->reMaterialize(*mbbi, mi, regA, regASubIdx, DefMI, *TRI);
- ReMatRegs.set(TargetRegisterInfo::virtReg2Index(regB));
- ++NumReMats;
- } else {
- BuildMI(*mbbi, mi, mi->getDebugLoc(), TII->get(TargetOpcode::COPY),
- regA).addReg(regB);
- isCopy = true;
- }
+ // Emit a copy.
+ BuildMI(*mbbi, mi, mi->getDebugLoc(), TII->get(TargetOpcode::COPY),
+ regA).addReg(regB);
// Update DistanceMap.
MachineBasicBlock::iterator prevMI = prior(mi);
@@ -1561,9 +1490,8 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &MF) {
MO.setReg(regA);
- if (isCopy)
- // Propagate SrcRegMap.
- SrcRegMap[regA] = regB;
+ // Propagate SrcRegMap.
+ SrcRegMap[regA] = regB;
}
if (AllUsesCopied) {
diff --git a/test/CodeGen/X86/cmov.ll b/test/CodeGen/X86/cmov.ll
index 43beac0b6f..ed25c82fdd 100644
--- a/test/CodeGen/X86/cmov.ll
+++ b/test/CodeGen/X86/cmov.ll
@@ -4,8 +4,8 @@ target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f3
define i32 @test1(i32 %x, i32 %n, i32 %w, i32* %vp) nounwind readnone {
entry:
; CHECK: test1:
-; CHECK: btl
-; CHECK-NEXT: movl $12, %eax
+; CHECK: movl $12, %eax
+; CHECK-NEXT: btl
; CHECK-NEXT: cmovael (%rcx), %eax
; CHECK-NEXT: ret
@@ -19,8 +19,8 @@ entry:
define i32 @test2(i32 %x, i32 %n, i32 %w, i32* %vp) nounwind readnone {
entry:
; CHECK: test2:
-; CHECK: btl
-; CHECK-NEXT: movl $12, %eax
+; CHECK: movl $12, %eax
+; CHECK-NEXT: btl
; CHECK-NEXT: cmovbl (%rcx), %eax
; CHECK-NEXT: ret
diff --git a/test/CodeGen/X86/jump_sign.ll b/test/CodeGen/X86/jump_sign.ll
index 5b7c19fec5..5fb6ee5254 100644
--- a/test/CodeGen/X86/jump_sign.ll
+++ b/test/CodeGen/X86/jump_sign.ll
@@ -142,6 +142,7 @@ if.else:
define i32 @l4(i32 %a, i32 %b) nounwind {
entry:
; CHECK: l4:
+; CHECK: xor
; CHECK: sub
; CHECK-NOT: cmp
%cmp = icmp sgt i32 %b, %a
diff --git a/test/CodeGen/X86/select.ll b/test/CodeGen/X86/select.ll
index c8d9345c40..ac9502873a 100644
--- a/test/CodeGen/X86/select.ll
+++ b/test/CodeGen/X86/select.ll
@@ -189,8 +189,8 @@ entry:
%call = tail call noalias i8* @_Znam(i64 %D) nounwind noredzone
ret i8* %call
; CHECK: test12:
-; CHECK: mulq
; CHECK: movq $-1, %rdi
+; CHECK: mulq
; CHECK: cmovnoq %rax, %rdi
; CHECK: jmp __Znam
}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2025-07-07 02:06:56 +0000