[llvm-commits] [llvm] r79369 - in /llvm/trunk: include/llvm/CodeGen/RegisterScavenging.h lib/CodeGen/RegisterScavenging.cpp lib/Target/ARM/ARMBaseRegisterInfo.cpp lib/Target/ARM/ARMLoadStoreOptimizer.cpp lib/Target/Blackfin/BlackfinRegisterInfo.cpp lib/Target/PowerPC/PPCRegisterInfo.cpp
Jakob Stoklund Olesen
stoklund at 2pi.dk
Tue Aug 18 14:14:54 PDT 2009
Author: stoklund
Date: Tue Aug 18 16:14:54 2009
New Revision: 79369
URL: http://llvm.org/viewvc/llvm-project?rev=79369&view=rev
Log:
Simplify RegScavenger::FindUnusedReg.
- Drop the Candidates argument and fix all callers. Now that RegScavenger
tracks available registers accurately, there is no need to restict the
search.
- Make sure that no aliases of the found register are in use. This was a potential bug.
Modified:
llvm/trunk/include/llvm/CodeGen/RegisterScavenging.h
llvm/trunk/lib/CodeGen/RegisterScavenging.cpp
llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp
llvm/trunk/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
llvm/trunk/lib/Target/Blackfin/BlackfinRegisterInfo.cpp
llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp
Modified: llvm/trunk/include/llvm/CodeGen/RegisterScavenging.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/RegisterScavenging.h?rev=79369&r1=79368&r2=79369&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/RegisterScavenging.h (original)
+++ llvm/trunk/include/llvm/CodeGen/RegisterScavenging.h Tue Aug 18 16:14:54 2009
@@ -98,15 +98,9 @@
/// getRegsUsed - return all registers currently in use in used.
void getRegsUsed(BitVector &used, bool includeReserved);
- /// FindUnusedReg - Find a unused register of the specified register class
- /// from the specified set of registers. It return 0 is none is found.
- unsigned FindUnusedReg(const TargetRegisterClass *RegClass,
- const BitVector &Candidates) const;
-
/// FindUnusedReg - Find a unused register of the specified register class.
- /// Exclude callee saved registers if directed. It return 0 is none is found.
- unsigned FindUnusedReg(const TargetRegisterClass *RegClass,
- bool ExCalleeSaved = false) const;
+ /// Return 0 if none is found.
+ unsigned FindUnusedReg(const TargetRegisterClass *RegClass) const;
/// setScavengingFrameIndex / getScavengingFrameIndex - accessor and setter of
/// ScavengingFrameIndex.
Modified: llvm/trunk/lib/CodeGen/RegisterScavenging.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/RegisterScavenging.cpp?rev=79369&r1=79368&r2=79369&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/RegisterScavenging.cpp (original)
+++ llvm/trunk/lib/CodeGen/RegisterScavenging.cpp Tue Aug 18 16:14:54 2009
@@ -248,36 +248,12 @@
Mask.set(*I);
}
-unsigned RegScavenger::FindUnusedReg(const TargetRegisterClass *RegClass,
- const BitVector &Candidates) const {
- // Mask off the registers which are not in the TargetRegisterClass.
- BitVector RegsAvailableCopy(NumPhysRegs, false);
- CreateRegClassMask(RegClass, RegsAvailableCopy);
- RegsAvailableCopy &= RegsAvailable;
-
- // Restrict the search to candidates.
- RegsAvailableCopy &= Candidates;
-
- // Returns the first unused (bit is set) register, or 0 is none is found.
- int Reg = RegsAvailableCopy.find_first();
- return (Reg == -1) ? 0 : Reg;
-}
-
-unsigned RegScavenger::FindUnusedReg(const TargetRegisterClass *RegClass,
- bool ExCalleeSaved) const {
- // Mask off the registers which are not in the TargetRegisterClass.
- BitVector RegsAvailableCopy(NumPhysRegs, false);
- CreateRegClassMask(RegClass, RegsAvailableCopy);
- RegsAvailableCopy &= RegsAvailable;
-
- // If looking for a non-callee-saved register, mask off all the callee-saved
- // registers.
- if (ExCalleeSaved)
- RegsAvailableCopy &= ~CalleeSavedRegs;
-
- // Returns the first unused (bit is set) register, or 0 is none is found.
- int Reg = RegsAvailableCopy.find_first();
- return (Reg == -1) ? 0 : Reg;
+unsigned RegScavenger::FindUnusedReg(const TargetRegisterClass *RC) const {
+ for (TargetRegisterClass::iterator I = RC->begin(), E = RC->end();
+ I != E; ++I)
+ if (!isAliasUsed(*I))
+ return *I;
+ return 0;
}
/// findSurvivorReg - Return the candidate register that is unused for the
Modified: llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp?rev=79369&r1=79368&r2=79369&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp Tue Aug 18 16:14:54 2009
@@ -1006,12 +1006,8 @@
static
unsigned findScratchRegister(RegScavenger *RS, const TargetRegisterClass *RC,
ARMFunctionInfo *AFI) {
- unsigned Reg = RS ? RS->FindUnusedReg(RC, true) : (unsigned) ARM::R12;
+ unsigned Reg = RS ? RS->FindUnusedReg(RC) : (unsigned) ARM::R12;
assert(!AFI->isThumb1OnlyFunction());
- if (Reg == 0)
- // Try a already spilled CS register.
- Reg = RS->FindUnusedReg(RC, AFI->getSpilledCSRegisters());
-
return Reg;
}
Modified: llvm/trunk/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMLoadStoreOptimizer.cpp?rev=79369&r1=79368&r2=79369&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMLoadStoreOptimizer.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMLoadStoreOptimizer.cpp Tue Aug 18 16:14:54 2009
@@ -941,12 +941,8 @@
// Try to find a free register to use as a new base in case it's needed.
// First advance to the instruction just before the start of the chain.
AdvanceRS(MBB, MemOps);
- // Find a scratch register. Make sure it's a call clobbered register or
- // a spilled callee-saved register.
- unsigned Scratch = RS->FindUnusedReg(&ARM::GPRRegClass, true);
- if (!Scratch)
- Scratch = RS->FindUnusedReg(&ARM::GPRRegClass,
- AFI->getSpilledCSRegisters());
+ // Find a scratch register.
+ unsigned Scratch = RS->FindUnusedReg(&ARM::GPRRegClass);
// Process the load / store instructions.
RS->forward(prior(MBBI));
Modified: llvm/trunk/lib/Target/Blackfin/BlackfinRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/Blackfin/BlackfinRegisterInfo.cpp?rev=79369&r1=79368&r2=79369&view=diff
==============================================================================
--- llvm/trunk/lib/Target/Blackfin/BlackfinRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/Blackfin/BlackfinRegisterInfo.cpp Tue Aug 18 16:14:54 2009
@@ -213,7 +213,7 @@
const TargetRegisterClass *RC,
int SPAdj) {
assert(RS && "Register scavenging must be on");
- unsigned Reg = RS->FindUnusedReg(RC, true);
+ unsigned Reg = RS->FindUnusedReg(RC);
if (Reg == 0)
Reg = RS->scavengeRegister(RC, II, SPAdj);
return Reg;
Modified: llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp?rev=79369&r1=79368&r2=79369&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCRegisterInfo.cpp Tue Aug 18 16:14:54 2009
@@ -527,7 +527,7 @@
unsigned findScratchRegister(MachineBasicBlock::iterator II, RegScavenger *RS,
const TargetRegisterClass *RC, int SPAdj) {
assert(RS && "Register scavenging must be on");
- unsigned Reg = RS->FindUnusedReg(RC, true);
+ unsigned Reg = RS->FindUnusedReg(RC);
// FIXME: move ARM callee-saved reg scan to target independent code, then
// search for already spilled CS register here.
if (Reg == 0)
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