GP-4899 Full check for switch target in isDoNothing

This commit is contained in:
caheckman 2024-09-30 23:02:15 +00:00
parent a3d0b40f36
commit 580226cfa0

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@ -2574,9 +2574,16 @@ bool BlockBasic::isDoNothing(void) const
if (sizeIn() == 0) return false; // A block that does nothing but
// is a starting block, may need to be a
// placeholder for global(persistent) vars
if ((sizeIn()==1)&&(getIn(0)->isSwitchOut())) {
if (getOut(0)->sizeIn() > 1)
return false; // Don't remove switch targets
for(int4 i=0;i<sizeIn();++i) {
const FlowBlock *switchbl = getIn(i);
if (!switchbl->isSwitchOut()) continue;
if (switchbl->sizeOut() > 1) {
// This block is a switch target
if (getOut(0)->sizeIn() > 1) { // Multiple edges coming together
// Switch edge may still be propagating a unique value
return false; // Don't remove it
}
}
}
PcodeOp *lastop = lastOp();
if ((lastop != (PcodeOp *)0)&&(lastop->code()==CPUI_BRANCHIND))