Change ARM VFP VLDM/VSTM instructions to use addressing mode #4, just like
all the other LDM/STM instructions. This fixes asm printer crashes when
compiling with -O0. I've changed one of the NEON tests (vst3.ll) to run
with -O0 to check this in the future.
Prior to this change VLDM/VSTM used addressing mode #5, but not really.
The offset field was used to hold a count of the number of registers being
loaded or stored, and the AM5 opcode field was expanded to specify the IA
or DB mode, instead of the standard ADD/SUB specifier. Much of the backend
was not aware of these special cases. The crashes occured when rewriting
a frameindex caused the AM5 offset field to be changed so that it did not
have a valid submode. I don't know exactly what changed to expose this now.
Maybe we've never done much with -O0 and NEON. Regardless, there's no longer
any reason to keep a count of the VLDM/VSTM registers, so we can use
addressing mode #4 and clean things up in a lot of places.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112322 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
index 2dbfb60..4fff738 100644
--- a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
+++ b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
@@ -193,18 +193,18 @@
return false;
ARM_AM::AMSubMode Mode = ARM_AM::ia;
- bool isAM4 = isi32Load(Opcode) || isi32Store(Opcode);
- if (isAM4 && Offset == 4) {
+ bool isNotVFP = isi32Load(Opcode) || isi32Store(Opcode);
+ if (isNotVFP && Offset == 4) {
if (isThumb2)
// Thumb2 does not support ldmib / stmib.
return false;
Mode = ARM_AM::ib;
- } else if (isAM4 && Offset == -4 * (int)NumRegs + 4) {
+ } else if (isNotVFP && Offset == -4 * (int)NumRegs + 4) {
if (isThumb2)
// Thumb2 does not support ldmda / stmda.
return false;
Mode = ARM_AM::da;
- } else if (isAM4 && Offset == -4 * (int)NumRegs) {
+ } else if (isNotVFP && Offset == -4 * (int)NumRegs) {
Mode = ARM_AM::db;
} else if (Offset != 0) {
// If starting offset isn't zero, insert a MI to materialize a new base.
@@ -246,18 +246,12 @@
BaseKill = true; // New base is always killed right its use.
}
- bool isDPR = (Opcode == ARM::VLDRD || Opcode == ARM::VSTRD);
bool isDef = (isi32Load(Opcode) || Opcode == ARM::VLDRS ||
Opcode == ARM::VLDRD);
Opcode = getLoadStoreMultipleOpcode(Opcode);
- MachineInstrBuilder MIB = (isAM4)
- ? BuildMI(MBB, MBBI, dl, TII->get(Opcode))
- .addReg(Base, getKillRegState(BaseKill))
- .addImm(ARM_AM::getAM4ModeImm(Mode)).addImm(Pred).addReg(PredReg)
- : BuildMI(MBB, MBBI, dl, TII->get(Opcode))
- .addReg(Base, getKillRegState(BaseKill))
- .addImm(ARM_AM::getAM5Opc(Mode, isDPR ? NumRegs<<1 : NumRegs))
- .addImm(Pred).addReg(PredReg);
+ MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII->get(Opcode))
+ .addReg(Base, getKillRegState(BaseKill))
+ .addImm(ARM_AM::getAM4ModeImm(Mode)).addImm(Pred).addReg(PredReg);
for (unsigned i = 0; i != NumRegs; ++i)
MIB = MIB.addReg(Regs[i].first, getDefRegState(isDef)
| getKillRegState(Regs[i].second));
@@ -348,7 +342,7 @@
ARMCC::CondCodes Pred, unsigned PredReg,
unsigned Scratch, MemOpQueue &MemOps,
SmallVector<MachineBasicBlock::iterator, 4> &Merges) {
- bool isAM4 = isi32Load(Opcode) || isi32Store(Opcode);
+ bool isNotVFP = isi32Load(Opcode) || isi32Store(Opcode);
int Offset = MemOps[SIndex].Offset;
int SOffset = Offset;
unsigned insertAfter = SIndex;
@@ -366,12 +360,12 @@
unsigned Reg = MO.getReg();
unsigned RegNum = MO.isUndef() ? UINT_MAX
: ARMRegisterInfo::getRegisterNumbering(Reg);
- // AM4 - register numbers in ascending order.
- // AM5 - consecutive register numbers in ascending order.
- // Can only do up to 16 double-word registers per insn.
+ // Register numbers must be in ascending order. For VFP, the registers
+ // must also be consecutive and there is a limit of 16 double-word
+ // registers per instruction.
if (Reg != ARM::SP &&
NewOffset == Offset + (int)Size &&
- ((isAM4 && RegNum > PRegNum)
+ ((isNotVFP && RegNum > PRegNum)
|| ((Size < 8 || Count < 16) && RegNum == PRegNum+1))) {
Offset += Size;
PRegNum = RegNum;
@@ -464,12 +458,11 @@
case ARM::STM:
case ARM::t2LDM:
case ARM::t2STM:
- return (MI->getNumOperands() - 4) * 4;
case ARM::VLDMS:
case ARM::VSTMS:
case ARM::VLDMD:
case ARM::VSTMD:
- return ARM_AM::getAM5Offset(MI->getOperand(1).getImm()) * 4;
+ return (MI->getNumOperands() - 4) * 4;
}
}
@@ -512,26 +505,17 @@
ARMCC::CondCodes Pred = llvm::getInstrPredicate(MI, PredReg);
int Opcode = MI->getOpcode();
DebugLoc dl = MI->getDebugLoc();
- bool isAM4 = (Opcode == ARM::LDM || Opcode == ARM::t2LDM ||
- Opcode == ARM::STM || Opcode == ARM::t2STM);
bool DoMerge = false;
ARM_AM::AMSubMode Mode = ARM_AM::ia;
- unsigned Offset = 0;
- if (isAM4) {
- // Can't use an updating ld/st if the base register is also a dest
- // register. e.g. ldmdb r0!, {r0, r1, r2}. The behavior is undefined.
- for (unsigned i = 3, e = MI->getNumOperands(); i != e; ++i) {
- if (MI->getOperand(i).getReg() == Base)
- return false;
- }
- Mode = ARM_AM::getAM4SubMode(MI->getOperand(1).getImm());
- } else {
- // VLDM{D|S}, VSTM{D|S} addressing mode 5 ops.
- Mode = ARM_AM::getAM5SubMode(MI->getOperand(1).getImm());
- Offset = ARM_AM::getAM5Offset(MI->getOperand(1).getImm());
+ // Can't use an updating ld/st if the base register is also a dest
+ // register. e.g. ldmdb r0!, {r0, r1, r2}. The behavior is undefined.
+ for (unsigned i = 3, e = MI->getNumOperands(); i != e; ++i) {
+ if (MI->getOperand(i).getReg() == Base)
+ return false;
}
+ Mode = ARM_AM::getAM4SubMode(MI->getOperand(1).getImm());
// Try merging with the previous instruction.
MachineBasicBlock::iterator BeginMBBI = MBB.begin();
@@ -539,22 +523,14 @@
MachineBasicBlock::iterator PrevMBBI = prior(MBBI);
while (PrevMBBI != BeginMBBI && PrevMBBI->isDebugValue())
--PrevMBBI;
- if (isAM4) {
- if (Mode == ARM_AM::ia &&
- isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
- DoMerge = true;
- Mode = ARM_AM::db;
- } else if (isAM4 && Mode == ARM_AM::ib &&
- isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
- DoMerge = true;
- Mode = ARM_AM::da;
- }
- } else {
- if (Mode == ARM_AM::ia &&
- isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
- Mode = ARM_AM::db;
- DoMerge = true;
- }
+ if (Mode == ARM_AM::ia &&
+ isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ Mode = ARM_AM::db;
+ DoMerge = true;
+ } else if (Mode == ARM_AM::ib &&
+ isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ Mode = ARM_AM::da;
+ DoMerge = true;
}
if (DoMerge)
MBB.erase(PrevMBBI);
@@ -566,19 +542,12 @@
MachineBasicBlock::iterator NextMBBI = llvm::next(MBBI);
while (NextMBBI != EndMBBI && NextMBBI->isDebugValue())
++NextMBBI;
- if (isAM4) {
- if ((Mode == ARM_AM::ia || Mode == ARM_AM::ib) &&
- isMatchingIncrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
- DoMerge = true;
- } else if ((Mode == ARM_AM::da || Mode == ARM_AM::db) &&
- isMatchingDecrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
- DoMerge = true;
- }
- } else {
- if (Mode == ARM_AM::ia &&
- isMatchingIncrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
- DoMerge = true;
- }
+ if ((Mode == ARM_AM::ia || Mode == ARM_AM::ib) &&
+ isMatchingIncrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ DoMerge = true;
+ } else if ((Mode == ARM_AM::da || Mode == ARM_AM::db) &&
+ isMatchingDecrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ DoMerge = true;
}
if (DoMerge) {
if (NextMBBI == I) {
@@ -595,16 +564,9 @@
unsigned NewOpc = getUpdatingLSMultipleOpcode(Opcode);
MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII->get(NewOpc))
.addReg(Base, getDefRegState(true)) // WB base register
- .addReg(Base, getKillRegState(BaseKill));
- if (isAM4) {
- // [t2]LDM_UPD, [t2]STM_UPD
- MIB.addImm(ARM_AM::getAM4ModeImm(Mode))
- .addImm(Pred).addReg(PredReg);
- } else {
- // VLDM[SD}_UPD, VSTM[SD]_UPD
- MIB.addImm(ARM_AM::getAM5Opc(Mode, Offset))
- .addImm(Pred).addReg(PredReg);
- }
+ .addReg(Base, getKillRegState(BaseKill))
+ .addImm(ARM_AM::getAM4ModeImm(Mode))
+ .addImm(Pred).addReg(PredReg);
// Transfer the rest of operands.
for (unsigned OpNum = 4, e = MI->getNumOperands(); OpNum != e; ++OpNum)
MIB.addOperand(MI->getOperand(OpNum));
@@ -736,11 +698,10 @@
if (!DoMerge)
return false;
- bool isDPR = NewOpc == ARM::VLDMD || NewOpc == ARM::VSTMD;
unsigned Offset = 0;
if (isAM5)
- Offset = ARM_AM::getAM5Opc(AddSub == ARM_AM::sub ? ARM_AM::db : ARM_AM::ia,
- (isDPR ? 2 : 1));
+ Offset = ARM_AM::getAM4ModeImm(AddSub == ARM_AM::sub ?
+ ARM_AM::db : ARM_AM::ia);
else if (isAM2)
Offset = ARM_AM::getAM2Opc(AddSub, Bytes, ARM_AM::no_shift);
else
@@ -748,6 +709,9 @@
if (isAM5) {
// VLDM[SD}_UPD, VSTM[SD]_UPD
+ // (There are no base-updating versions of VLDR/VSTR instructions, but the
+ // updating load/store-multiple instructions can be used with only one
+ // register.)
MachineOperand &MO = MI->getOperand(0);
BuildMI(MBB, MBBI, dl, TII->get(NewOpc))
.addReg(Base, getDefRegState(true)) // WB base register