If there are multiple register classes that a register belongs to, return the super-class (e.g. on x86, returns GR32, not GR32_).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48220 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2008-03-11 07:54:14 +00:00
parent 9a8094159d
commit fa2f786f4e

View File

@ -33,6 +33,17 @@ TargetRegisterInfo::TargetRegisterInfo(const TargetRegisterDesc *D, unsigned NR,
TargetRegisterInfo::~TargetRegisterInfo() {}
namespace {
// Sort according to super- / sub- class relations.
// i.e. super- register class < sub- register class.
struct RCCompare {
bool operator()(const TargetRegisterClass* const &LHS,
const TargetRegisterClass* const &RHS) {
return RHS->hasSuperClass(LHS);
}
};
}
/// getPhysicalRegisterRegClass - Returns the Register Class of a physical
/// register of the given type. If type is MVT::Other, then just return any
/// register class the register belongs to.
@ -40,11 +51,23 @@ const TargetRegisterClass *
TargetRegisterInfo::getPhysicalRegisterRegClass(unsigned reg,
MVT::ValueType VT) const {
assert(isPhysicalRegister(reg) && "reg must be a physical register");
// Pick the register class of the right type that contains this physreg.
for (regclass_iterator I = regclass_begin(), E = regclass_end(); I != E; ++I)
if ((VT == MVT::Other || (*I)->hasType(VT))
&& (*I)->contains(reg))
return *I;
SmallVector<const TargetRegisterClass*, 4> RCs;
for (regclass_iterator I = regclass_begin(), E = regclass_end(); I != E; ++I) {
if ((VT == MVT::Other || (*I)->hasType(VT)) && (*I)->contains(reg))
RCs.push_back(*I);
}
if (RCs.size() == 1)
return RCs[0];
if (RCs.size()) {
// Multiple compatible register classes. Get the super- class.
std::stable_sort(RCs.begin(), RCs.end(), RCCompare());
return RCs[0];
}
assert(false && "Couldn't find the register class");
return 0;
}