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More IT instruction error-handling improvements from fuzzing.

llvm-svn: 101839
This commit is contained in:
Johnny Chen 2010-04-20 00:15:41 +00:00
parent 744e2b34b0
commit 1b36569ba8

View File

@ -513,7 +513,7 @@ static unsigned short CountITSize(unsigned ITMask) {
// First count the trailing zeros of the IT mask.
unsigned TZ = CountTrailingZeros_32(ITMask);
if (TZ > 3) {
DEBUG(errs() << "Encoding error of IT mask");
DEBUG(errs() << "Encoding error: IT Mask '0000'");
return 0;
}
return (4 - TZ);
@ -522,9 +522,23 @@ static unsigned short CountITSize(unsigned ITMask) {
/// Init ITState. Note that at least one bit is always 1 in mask.
bool Session::InitIT(unsigned short bits7_0) {
ITCounter = CountITSize(slice(bits7_0, 3, 0));
if (ITCounter == 0)
return false;
// A8.6.50 IT
unsigned short FirstCond = slice(bits7_0, 7, 4);
if (FirstCond == 0xF) {
DEBUG(errs() << "Encoding error: IT FirstCond '1111'");
return false;
}
if (FirstCond == 0xE && ITCounter != 1) {
DEBUG(errs() << "Encoding error: IT FirstCond '1110' && Mask != '1000'");
return false;
}
ITState = bits7_0;
// Only need to check for > 0.
return ITCounter > 0;
return true;
}
/// Update ITState if necessary.