x86: create function to check miscreg validity

In the process of trying to get rid of an '== false' comparison,
it became apparent that a slightly more involved solution was
needed.  Split this out into its own changeset since it's not
a totally trivial local change like the others.
This commit is contained in:
Steve Reinhardt 2016-02-06 17:21:20 -08:00
parent 4e65e25e25
commit 2d91e741e8
3 changed files with 14 additions and 19 deletions

View file

@ -129,13 +129,7 @@ ISA::readMiscRegNoEffect(int miscReg) const
// Make sure we're not dealing with an illegal control register.
// Instructions should filter out these indexes, and nothing else should
// attempt to read them directly.
assert(miscReg >= MISCREG_CR0 &&
miscReg < NUM_MISCREGS &&
miscReg != MISCREG_CR1 &&
!(miscReg > MISCREG_CR4 &&
miscReg < MISCREG_CR8) &&
!(miscReg > MISCREG_CR8 &&
miscReg <= MISCREG_CR15));
assert(isValidMiscReg(miscReg));
return regVal[miscReg];
}
@ -162,13 +156,7 @@ ISA::setMiscRegNoEffect(int miscReg, MiscReg val)
// Make sure we're not dealing with an illegal control register.
// Instructions should filter out these indexes, and nothing else should
// attempt to write to them directly.
assert(miscReg >= MISCREG_CR0 &&
miscReg < NUM_MISCREGS &&
miscReg != MISCREG_CR1 &&
!(miscReg > MISCREG_CR4 &&
miscReg < MISCREG_CR8) &&
!(miscReg > MISCREG_CR8 &&
miscReg <= MISCREG_CR15));
assert(isValidMiscReg(miscReg));
HandyM5Reg m5Reg = readMiscRegNoEffect(MISCREG_M5_REG);
switch (miscReg) {

View file

@ -101,7 +101,7 @@ namespace X86ISA
enum MiscRegIndex
{
// Control registers
// Most of these are invalid.
// Most of these are invalid. See isValidMiscReg() below.
MISCREG_CR_BASE,
MISCREG_CR0 = MISCREG_CR_BASE,
MISCREG_CR1,
@ -399,6 +399,15 @@ namespace X86ISA
NUM_MISCREGS
};
static inline bool
isValidMiscReg(int index)
{
return (index >= MISCREG_CR0 && index < NUM_MISCREGS &&
index != MISCREG_CR1 &&
!(index > MISCREG_CR4 && index < MISCREG_CR8) &&
!(index > MISCREG_CR8 && index <= MISCREG_CR15));
}
static inline MiscRegIndex
MISCREG_CR(int index)
{

View file

@ -217,11 +217,9 @@ copyMiscRegs(ThreadContext *src, ThreadContext *dest)
// need to be considered while copying state. That will likely not be
// true in the future.
for (int i = 0; i < NUM_MISCREGS; ++i) {
if ( ( i != MISCREG_CR1 &&
!(i > MISCREG_CR4 && i < MISCREG_CR8) &&
!(i > MISCREG_CR8 && i <= MISCREG_CR15) ) == false) {
if (!isValidMiscReg(i))
continue;
}
dest->setMiscRegNoEffect(i, src->readMiscRegNoEffect(i));
}