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ARM: Clean up use of TBit and JBit.

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Rather tha constantly using ULL(1) << PcXBitShift define those directly.
Additionally, add some helper functions to further clean up the code.
This commit is contained in:
Ali Saidi 2010-10-01 16:02:45 -05:00
parent aef4a9904e
commit b331b02669
9 changed files with 31 additions and 25 deletions
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2
src/arch/arm/faults.cc
View file

@ -140,7 +140,7 @@ ArmFault::invoke(ThreadContext *tc, StaticInstPtr inst)
}
Addr pc M5_VAR_USED = tc->readPC();
Addr newPc = getVector(tc) | (sctlr.te ? (ULL(1) << PcTBitShift) : 0);
Addr newPc = getVector(tc) | (sctlr.te ? PcTBit : 0);
DPRINTF(Faults, "Invoking Fault:%s cpsr:%#x PC:%#x lr:%#x newVec: %#x\n",
name(), cpsr, pc, tc->readIntReg(INTREG_LR), newPc);
tc->setPC(newPc);

14
src/arch/arm/insts/static_inst.hh
View file

@ -43,6 +43,7 @@
#define __ARCH_ARM_INSTS_STATICINST_HH__
#include "arch/arm/faults.hh"
#include "arch/arm/utility.hh"
#include "base/trace.hh"
#include "cpu/static_inst.hh"
@ -219,8 +220,7 @@ class ArmStaticInst : public StaticInst
readPC(XC *xc)
{
Addr pc = xc->readPC();
Addr tBit = pc & (ULL(1) << PcTBitShift);
if (tBit)
if (isThumb(pc))
return pc + 4;
else
return pc + 8;
@ -232,7 +232,7 @@ class ArmStaticInst : public StaticInst
setNextPC(XC *xc, Addr val)
{
Addr npc = xc->readNextPC();
if (npc & (ULL(1) << PcTBitShift)) {
if (isThumb(npc)) {
val &= ~mask(1);
} else {
val &= ~mask(2);
@ -280,8 +280,8 @@ class ArmStaticInst : public StaticInst
setIWNextPC(XC *xc, Addr val)
{
Addr stateBits = xc->readPC() & PcModeMask;
Addr jBit = (ULL(1) << PcJBitShift);
Addr tBit = (ULL(1) << PcTBitShift);
Addr jBit = PcJBit;
Addr tBit = PcTBit;
bool thumbEE = (stateBits == (tBit | jBit));
Addr newPc = (val & ~PcModeMask);
@ -312,8 +312,8 @@ class ArmStaticInst : public StaticInst
setAIWNextPC(XC *xc, Addr val)
{
Addr stateBits = xc->readPC() & PcModeMask;
Addr jBit = (ULL(1) << PcJBitShift);
Addr tBit = (ULL(1) << PcTBitShift);
Addr jBit = PcJBit;
Addr tBit = PcTBit;
if (!jBit && !tBit) {
setIWNextPC(xc, val);
} else {

6
src/arch/arm/isa.cc
View file

@ -173,7 +173,7 @@ ISA::readMiscReg(int misc_reg, ThreadContext *tc)
cpsr.j = 1;
else
cpsr.j = 0;
if (pc & (ULL(1) << PcTBitShift))
if (isThumb(pc))
cpsr.t = 1;
else
cpsr.t = 0;
@ -241,9 +241,9 @@ ISA::setMiscReg(int misc_reg, const MiscReg &val, ThreadContext *tc)
miscRegs[misc_reg], cpsr, cpsr.f, cpsr.i, cpsr.a, cpsr.mode);
Addr npc = tc->readNextPC() & ~PcModeMask;
if (cpsr.j)
npc = npc | (ULL(1) << PcJBitShift);
npc = npc | PcJBit;
if (cpsr.t)
npc = npc | (ULL(1) << PcTBitShift);
npc = npc | PcTBit;
tc->setNextPC(npc);
} else if (misc_reg >= MISCREG_CP15_UNIMP_START &&

16
src/arch/arm/isa/insts/branch.isa
View file

@ -51,8 +51,7 @@ let {{
'''
if (link):
bCode += '''
Addr tBit = curPc & (ULL(1) << PcTBitShift);
if (!tBit)
if (!isThumb(curPc))
LR = curPc - 4;
else
LR = curPc | 1;
@ -67,10 +66,7 @@ let {{
# BX, BLX
blxCode = '''
Addr curPc = readPC(xc);
Addr tBit = curPc & (ULL(1) << PcTBitShift);
bool arm = !tBit;
arm = arm; // In case it's not used otherwise.
Addr curPc M5_VAR_USED = readPC(xc);
%(link)s
// Switch modes
%(branch)s
@ -86,7 +82,7 @@ let {{
Name += "Imm"
# Since we're switching ISAs, the target ISA will be the opposite
# of the current ISA. !arm is whether the target is ARM.
newPC = '(!arm ? (roundDown(curPc, 4) + imm) : (curPc + imm))'
newPC = '(isThumb(curPc) ? (roundDown(curPc, 4) + imm) : (curPc + imm))'
base = "BranchImmCond"
declare = BranchImmCondDeclare
constructor = BranchImmCondConstructor
@ -101,14 +97,14 @@ let {{
// The immediate version of the blx thumb instruction
// is 32 bits wide, but "next pc" doesn't reflect that
// so we don't want to substract 2 from it at this point
if (arm)
if (!isThumb(curPc))
LR = curPc - 4;
else
LR = curPc | 1;
'''
elif link:
linkStr = '''
if (arm)
if (!isThumb(curPc))
LR = curPc - 4;
else
LR = (curPc - 2) | 1;
@ -119,7 +115,7 @@ let {{
if imm and link: #blx with imm
branchStr = '''
Addr tempPc = ((%(newPC)s) & mask(32)) | (curPc & ~mask(32));
FNPC = tempPc ^ (ULL(1) << PcTBitShift);
FNPC = tempPc ^ PcTBit;
'''
else:
branchStr = "IWNPC = %(newPC)s;"

4
src/arch/arm/isa/insts/misc.isa
View file

@ -638,7 +638,7 @@ let {{
exec_output += PredOpExecute.subst(mcr15UserIop)
enterxCode = '''
FNPC = NPC | (1ULL << PcJBitShift) | (1ULL << PcTBitShift);
FNPC = NPC | PcJBit | PcTBit;
'''
enterxIop = InstObjParams("enterx", "Enterx", "PredOp",
{ "code": enterxCode,
@ -648,7 +648,7 @@ let {{
exec_output += PredOpExecute.subst(enterxIop)
leavexCode = '''
FNPC = (NPC & ~(1ULL << PcJBitShift)) | (1ULL << PcTBitShift);
FNPC = (NPC & ~PcJBit) | PcTBit;
'''
leavexIop = InstObjParams("leavex", "Leavex", "PredOp",
{ "code": leavexCode,

2
src/arch/arm/isa_traits.hh
View file

@ -127,7 +127,9 @@ namespace ArmISA
// These otherwise unused bits of the PC are used to select a mode
// like the J and T bits of the CPSR.
static const Addr PcJBitShift = 33;
static const Addr PcJBit = ULL(1) << PcJBitShift;
static const Addr PcTBitShift = 34;
static const Addr PcTBit = ULL(1) << PcTBitShift;
static const Addr PcModeMask = (ULL(1) << PcJBitShift) |
(ULL(1) << PcTBitShift);
};

3
src/arch/arm/predecoder.cc
View file

@ -43,6 +43,7 @@
#include "arch/arm/isa_traits.hh"
#include "arch/arm/predecoder.hh"
#include "arch/arm/utility.hh"
#include "base/trace.hh"
#include "cpu/thread_context.hh"
@ -151,7 +152,7 @@ Predecoder::moreBytes(Addr pc, Addr fetchPC, MachInst inst)
{
data = inst;
offset = (fetchPC >= pc) ? 0 : pc - fetchPC;
emi.thumb = (pc & (ULL(1) << PcTBitShift)) ? 1 : 0;
emi.thumb = isThumb(pc);
FPSCR fpscr = tc->readMiscReg(MISCREG_FPSCR);
emi.fpscrLen = fpscr.len;
emi.fpscrStride = fpscr.stride;

2
src/arch/arm/process.cc
View file

@ -362,7 +362,7 @@ ArmLiveProcess::argsInit(int intSize, int pageSize)
Addr prog_entry = objFile->entryPoint();
if (arch == ObjectFile::Thumb)
prog_entry = (prog_entry & ~mask(1)) | (ULL(1) << PcTBitShift);
prog_entry = (prog_entry & ~mask(1)) | PcTBit;
tc->setPC(prog_entry);
tc->setNextPC(prog_entry + sizeof(MachInst));

7
src/arch/arm/utility.hh
View file

@ -45,6 +45,7 @@
#ifndef __ARCH_ARM_UTILITY_HH__
#define __ARCH_ARM_UTILITY_HH__
#include "arch/arm/isa_traits.hh"
#include "arch/arm/miscregs.hh"
#include "arch/arm/types.hh"
#include "base/misc.hh"
@ -92,6 +93,12 @@ namespace ArmISA {
tc->activate(0);
}
static inline bool
isThumb(Addr pc)
{
return (pc & PcTBit);
}
static inline void
copyRegs(ThreadContext *src, ThreadContext *dest)
{