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-rw-r--r--lib/CodeGen/RegAllocFast.cpp58
1 files changed, 28 insertions, 30 deletions
diff --git a/lib/CodeGen/RegAllocFast.cpp b/lib/CodeGen/RegAllocFast.cpp
index 15036e3..65ebdf8 100644
--- a/lib/CodeGen/RegAllocFast.cpp
+++ b/lib/CodeGen/RegAllocFast.cpp
@@ -13,6 +13,7 @@
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "regalloc"
+#include "RegisterClassInfo.h"
#include "llvm/BasicBlock.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
@@ -58,6 +59,7 @@ namespace {
MachineRegisterInfo *MRI;
const TargetRegisterInfo *TRI;
const TargetInstrInfo *TII;
+ RegisterClassInfo RegClassInfo;
// Basic block currently being allocated.
MachineBasicBlock *MBB;
@@ -97,7 +99,7 @@ namespace {
// immediately without checking aliases.
regFree,
- // A reserved register has been assigned expolicitly (e.g., setting up a
+ // A reserved register has been assigned explicitly (e.g., setting up a
// call parameter), and it remains reserved until it is used.
regReserved
@@ -113,9 +115,6 @@ namespace {
// instruction, and so cannot be allocated.
BitVector UsedInInstr;
- // Allocatable - vector of allocatable physical registers.
- BitVector Allocatable;
-
// SkippedInstrs - Descriptors of instructions whose clobber list was
// ignored because all registers were spilled. It is still necessary to
// mark all the clobbered registers as used by the function.
@@ -396,7 +395,6 @@ void RAFast::definePhysReg(MachineInstr *MI, unsigned PhysReg,
PhysRegState[PhysReg] = NewState;
for (const unsigned *AS = TRI->getAliasSet(PhysReg);
unsigned Alias = *AS; ++AS) {
- UsedInInstr.set(Alias);
switch (unsigned VirtReg = PhysRegState[Alias]) {
case regDisabled:
break;
@@ -420,20 +418,25 @@ void RAFast::definePhysReg(MachineInstr *MI, unsigned PhysReg,
// can be allocated directly.
// Returns spillImpossible when PhysReg or an alias can't be spilled.
unsigned RAFast::calcSpillCost(unsigned PhysReg) const {
- if (UsedInInstr.test(PhysReg))
+ if (UsedInInstr.test(PhysReg)) {
+ DEBUG(dbgs() << "PhysReg: " << PhysReg << " is already used in instr.\n");
return spillImpossible;
+ }
switch (unsigned VirtReg = PhysRegState[PhysReg]) {
case regDisabled:
break;
case regFree:
return 0;
case regReserved:
+ DEBUG(dbgs() << "VirtReg: " << VirtReg << " corresponding to PhysReg: "
+ << PhysReg << " is reserved already.\n");
return spillImpossible;
default:
return LiveVirtRegs.lookup(VirtReg).Dirty ? spillDirty : spillClean;
}
- // This is a disabled register, add up const of aliases.
+ // This is a disabled register, add up cost of aliases.
+ DEBUG(dbgs() << "\tRegister: " << PhysReg << " is disabled.\n");
unsigned Cost = 0;
for (const unsigned *AS = TRI->getAliasSet(PhysReg);
unsigned Alias = *AS; ++AS) {
@@ -479,30 +482,26 @@ void RAFast::allocVirtReg(MachineInstr *MI, LiveRegEntry &LRE, unsigned Hint) {
// Ignore invalid hints.
if (Hint && (!TargetRegisterInfo::isPhysicalRegister(Hint) ||
- !RC->contains(Hint) || !Allocatable.test(Hint)))
+ !RC->contains(Hint) || !RegClassInfo.isAllocatable(Hint)))
Hint = 0;
// Take hint when possible.
if (Hint) {
- switch(calcSpillCost(Hint)) {
- default:
- definePhysReg(MI, Hint, regFree);
- // Fall through.
- case 0:
+ // Ignore the hint if we would have to spill a dirty register.
+ unsigned Cost = calcSpillCost(Hint);
+ if (Cost < spillDirty) {
+ if (Cost)
+ definePhysReg(MI, Hint, regFree);
return assignVirtToPhysReg(LRE, Hint);
- case spillImpossible:
- break;
}
}
- TargetRegisterClass::iterator AOB = RC->allocation_order_begin(*MF);
- TargetRegisterClass::iterator AOE = RC->allocation_order_end(*MF);
+ ArrayRef<unsigned> AO = RegClassInfo.getOrder(RC);
// First try to find a completely free register.
- for (TargetRegisterClass::iterator I = AOB; I != AOE; ++I) {
+ for (ArrayRef<unsigned>::iterator I = AO.begin(), E = AO.end(); I != E; ++I) {
unsigned PhysReg = *I;
- if (PhysRegState[PhysReg] == regFree && !UsedInInstr.test(PhysReg) &&
- Allocatable.test(PhysReg))
+ if (PhysRegState[PhysReg] == regFree && !UsedInInstr.test(PhysReg))
return assignVirtToPhysReg(LRE, PhysReg);
}
@@ -510,10 +509,11 @@ void RAFast::allocVirtReg(MachineInstr *MI, LiveRegEntry &LRE, unsigned Hint) {
<< RC->getName() << "\n");
unsigned BestReg = 0, BestCost = spillImpossible;
- for (TargetRegisterClass::iterator I = AOB; I != AOE; ++I) {
- if (!Allocatable.test(*I))
- continue;
+ for (ArrayRef<unsigned>::iterator I = AO.begin(), E = AO.end(); I != E; ++I) {
unsigned Cost = calcSpillCost(*I);
+ DEBUG(dbgs() << "\tRegister: " << *I << "\n");
+ DEBUG(dbgs() << "\tCost: " << Cost << "\n");
+ DEBUG(dbgs() << "\tBestCost: " << BestCost << "\n");
// Cost is 0 when all aliases are already disabled.
if (Cost == 0)
return assignVirtToPhysReg(LRE, *I);
@@ -722,9 +722,8 @@ void RAFast::handleThroughOperands(MachineInstr *MI,
if (!MO.isReg() || (MO.isDef() && !MO.isEarlyClobber())) continue;
unsigned Reg = MO.getReg();
if (!Reg || !TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
+ DEBUG(dbgs() << "\tSetting reg " << Reg << " as used in instr\n");
UsedInInstr.set(Reg);
- for (const unsigned *AS = TRI->getAliasSet(Reg); *AS; ++AS)
- UsedInInstr.set(*AS);
}
// Also mark PartialDefs as used to avoid reallocation.
@@ -764,7 +763,7 @@ void RAFast::AllocateBasicBlock() {
// Add live-in registers as live.
for (MachineBasicBlock::livein_iterator I = MBB->livein_begin(),
E = MBB->livein_end(); I != E; ++I)
- if (Allocatable.test(*I))
+ if (RegClassInfo.isAllocatable(*I))
definePhysReg(MII, *I, regReserved);
SmallVector<unsigned, 8> VirtDead;
@@ -895,7 +894,7 @@ void RAFast::AllocateBasicBlock() {
}
continue;
}
- if (!Allocatable.test(Reg)) continue;
+ if (!RegClassInfo.isAllocatable(Reg)) continue;
if (MO.isUse()) {
usePhysReg(MO);
} else if (MO.isEarlyClobber()) {
@@ -984,7 +983,7 @@ void RAFast::AllocateBasicBlock() {
unsigned Reg = MO.getReg();
if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
- if (!Allocatable.test(Reg)) continue;
+ if (!RegClassInfo.isAllocatable(Reg)) continue;
definePhysReg(MI, Reg, (MO.isImplicit() || MO.isDead()) ?
regFree : regReserved);
continue;
@@ -1040,9 +1039,8 @@ bool RAFast::runOnMachineFunction(MachineFunction &Fn) {
TM = &Fn.getTarget();
TRI = TM->getRegisterInfo();
TII = TM->getInstrInfo();
-
+ RegClassInfo.runOnMachineFunction(Fn);
UsedInInstr.resize(TRI->getNumRegs());
- Allocatable = TRI->getAllocatableSet(*MF);
// initialize the virtual->physical register map to have a 'null'
// mapping for all virtual registers
generated by cgit v1.1 at 2025-07-03 18:36:52 +0000