RPCS3/llvm
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm.git synced 2024-12-14 07:31:53 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Match live variable changes.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31762 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2006-11-15 20:55:15 +00:00
parent 6b2c05f3d3
commit ddee842062
1 changed files with 56 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

66
lib/CodeGen/RegAllocLocal.cpp
View File

@ -13,6 +13,7 @@
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "regalloc"
#include "llvm/BasicBlock.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
@ -26,6 +27,7 @@
#include "llvm/Support/Debug.h"
#include "llvm/Support/Compiler.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include <algorithm>
#include <iostream>
@ -309,7 +311,18 @@ void RA::spillPhysReg(MachineBasicBlock &MBB, MachineInstr *I,
*AliasSet; ++AliasSet)
if (PhysRegsUsed[*AliasSet] != -1 && // Spill aliased register.
PhysRegsUsed[*AliasSet] != -2) // If allocatable.
if (PhysRegsUsed[*AliasSet] || !OnlyVirtRegs)
if (PhysRegsUsed[*AliasSet] == 0) {
// This must have been a dead def due to something like this:
// %EAX :=
// := op %AL
// No more use of %EAX, %AH, etc.
// %EAX isn't dead upon definition, but %AH is. However %AH isn't
// an operand of definition MI so it's not marked as such.
DEBUG(std::cerr << " Register " << RegInfo->getName(*AliasSet)
<< " [%reg" << *AliasSet
<< "] is never used, removing it frame live list\n");
removePhysReg(*AliasSet);
} else
spillVirtReg(MBB, I, PhysRegsUsed[*AliasSet], *AliasSet);
}
}
@ -512,6 +525,9 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
MachineBasicBlock::iterator MII = MBB.begin();
const TargetInstrInfo &TII = *TM->getInstrInfo();
DEBUG(const BasicBlock *LBB = MBB.getBasicBlock();
if (LBB) std::cerr << "\nStarting RegAlloc of BB: " << LBB->getName());
// If this is the first basic block in the machine function, add live-in
// registers as active.
if (&MBB == &*MF->begin()) {
@ -552,6 +568,13 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
MarkPhysRegRecentlyUsed(*ImplicitUses);
}
SmallVector<unsigned, 8> Kills;
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
MachineOperand& MO = MI->getOperand(i);
if (MO.isRegister() && MO.isKill())
Kills.push_back(MO.getReg());
}
// Get the used operands into registers. This has the potential to spill
// incoming values if we are out of registers. Note that we completely
// ignore physical register uses here. We assume that if an explicit
@ -561,18 +584,17 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
for (unsigned i = 0; i != MI->getNumOperands(); ++i) {
MachineOperand& MO = MI->getOperand(i);
// here we are looking for only used operands (never def&use)
if (MO.isRegister() && !MO.isDef() && !MO.isImplicit() && MO.getReg() &&
if (MO.isRegister() && !MO.isDef() && MO.getReg() && !MO.isImplicit() &&
MRegisterInfo::isVirtualRegister(MO.getReg()))
MI = reloadVirtReg(MBB, MI, i);
}
// If this instruction is the last user of anything in registers, kill the
// If this instruction is the last user of this register, kill the
// value, freeing the register being used, so it doesn't need to be
// spilled to memory.
//
for (LiveVariables::killed_iterator KI = LV->killed_begin(MI),
KE = LV->killed_end(MI); KI != KE; ++KI) {
unsigned VirtReg = *KI;
for (unsigned i = 0, e = Kills.size(); i != e; ++i) {
unsigned VirtReg = Kills[i];
unsigned PhysReg = VirtReg;
if (MRegisterInfo::isVirtualRegister(VirtReg)) {
// If the virtual register was never materialized into a register, it
@ -589,6 +611,15 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
DEBUG(std::cerr << " Last use of " << RegInfo->getName(PhysReg)
<< "[%reg" << VirtReg <<"], removing it from live set\n");
removePhysReg(PhysReg);
for (const unsigned *AliasSet = RegInfo->getAliasSet(PhysReg);
*AliasSet; ++AliasSet) {
if (PhysRegsUsed[*AliasSet] != -2) {
DEBUG(std::cerr << " Last use of "
<< RegInfo->getName(*AliasSet)
<< "[%reg" << VirtReg <<"], removing it from live set\n");
removePhysReg(*AliasSet);
}
}
}
}
@ -602,7 +633,7 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
if (PhysRegsUsed[Reg] == -2) continue; // Something like ESP.
PhysRegsEverUsed[Reg] = true;
spillPhysReg(MBB, MI, Reg, true); // Spill any existing value in the reg
spillPhysReg(MBB, MI, Reg, true); // Spill any existing value in reg
PhysRegsUsed[Reg] = 0; // It is free and reserved now
PhysRegsUseOrder.push_back(Reg);
for (const unsigned *AliasSet = RegInfo->getAliasSet(Reg);
@ -642,6 +673,13 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
}
}
SmallVector<unsigned, 8> DeadDefs;
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
MachineOperand& MO = MI->getOperand(i);
if (MO.isRegister() && MO.isDead())
DeadDefs.push_back(MO.getReg());
}
// Okay, we have allocated all of the source operands and spilled any values
// that would be destroyed by defs of this instruction. Loop over the
// explicit defs and assign them to a register, spilling incoming values if
@ -666,9 +704,8 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
// If this instruction defines any registers that are immediately dead,
// kill them now.
//
for (LiveVariables::killed_iterator KI = LV->dead_begin(MI),
KE = LV->dead_end(MI); KI != KE; ++KI) {
unsigned VirtReg = *KI;
for (unsigned i = 0, e = DeadDefs.size(); i != e; ++i) {
unsigned VirtReg = DeadDefs[i];
unsigned PhysReg = VirtReg;
if (MRegisterInfo::isVirtualRegister(VirtReg)) {
unsigned &PhysRegSlot = getVirt2PhysRegMapSlot(VirtReg);
@ -685,6 +722,15 @@ void RA::AllocateBasicBlock(MachineBasicBlock &MBB) {
<< " [%reg" << VirtReg
<< "] is never used, removing it frame live list\n");
removePhysReg(PhysReg);
for (const unsigned *AliasSet = RegInfo->getAliasSet(PhysReg);
*AliasSet; ++AliasSet) {
if (PhysRegsUsed[*AliasSet] != -2) {
DEBUG(std::cerr << " Register " << RegInfo->getName(*AliasSet)
<< " [%reg" << *AliasSet
<< "] is never used, removing it frame live list\n");
removePhysReg(*AliasSet);
}
}
}
}