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Use std::bitset for SubtargetFeatures

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Previously, subtarget features were a bitfield with the underlying type being uint64_t. 
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.

The first time this was committed (r229831), it caused several buildbot failures. 
At least some of the ARM ones were due to gcc/binutils issues, and should now be fixed.

Differential Revision: http://reviews.llvm.org/D8542

llvm-svn: 233055
This commit is contained in:
Michael Kuperstein
2015-03-24 09:17:25 +00:00
parent 25122a3c57
commit 774b441b5e
33 changed files with 348 additions and 308 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
llvm/lib/MC/SubtargetFeature.cpp
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@@ -150,12 +150,12 @@ std::string SubtargetFeatures::getString() const {
/// feature, set it.
///
static
void SetImpliedBits(uint64_t &Bits, const SubtargetFeatureKV *FeatureEntry,
void SetImpliedBits(FeatureBitset &Bits, const SubtargetFeatureKV *FeatureEntry,
ArrayRef<SubtargetFeatureKV> FeatureTable) {
for (auto &FE : FeatureTable) {
if (FeatureEntry->Value == FE.Value) continue;
if (FeatureEntry->Implies & FE.Value) {
if ((FeatureEntry->Implies & FE.Value).any()) {
Bits |= FE.Value;
SetImpliedBits(Bits, &FE, FeatureTable);
}
@@ -166,12 +166,13 @@ void SetImpliedBits(uint64_t &Bits, const SubtargetFeatureKV *FeatureEntry,
/// feature, clear it.
///
static
void ClearImpliedBits(uint64_t &Bits, const SubtargetFeatureKV *FeatureEntry,
void ClearImpliedBits(FeatureBitset &Bits,
const SubtargetFeatureKV *FeatureEntry,
ArrayRef<SubtargetFeatureKV> FeatureTable) {
for (auto &FE : FeatureTable) {
if (FeatureEntry->Value == FE.Value) continue;
if (FE.Implies & FeatureEntry->Value) {
if ((FE.Implies & FeatureEntry->Value).any()) {
Bits &= ~FE.Value;
ClearImpliedBits(Bits, &FE, FeatureTable);
}
@@ -180,8 +181,8 @@ void ClearImpliedBits(uint64_t &Bits, const SubtargetFeatureKV *FeatureEntry,
/// ToggleFeature - Toggle a feature and returns the newly updated feature
/// bits.
uint64_t
SubtargetFeatures::ToggleFeature(uint64_t Bits, StringRef Feature,
FeatureBitset
SubtargetFeatures::ToggleFeature(FeatureBitset Bits, StringRef Feature,
ArrayRef<SubtargetFeatureKV> FeatureTable) {
// Find feature in table.
@@ -191,7 +192,6 @@ SubtargetFeatures::ToggleFeature(uint64_t Bits, StringRef Feature,
if (FeatureEntry) {
if ((Bits & FeatureEntry->Value) == FeatureEntry->Value) {
Bits &= ~FeatureEntry->Value;
// For each feature that implies this, clear it.
ClearImpliedBits(Bits, FeatureEntry, FeatureTable);
} else {
@@ -212,13 +212,13 @@ SubtargetFeatures::ToggleFeature(uint64_t Bits, StringRef Feature,
/// getFeatureBits - Get feature bits a CPU.
///
uint64_t
FeatureBitset
SubtargetFeatures::getFeatureBits(StringRef CPU,
ArrayRef<SubtargetFeatureKV> CPUTable,
ArrayRef<SubtargetFeatureKV> FeatureTable) {
if (CPUTable.empty() || FeatureTable.empty())
return 0;
return FeatureBitset();
#ifndef NDEBUG
for (size_t i = 1, e = CPUTable.size(); i != e; ++i) {
@@ -230,7 +230,8 @@ SubtargetFeatures::getFeatureBits(StringRef CPU,
"CPU features table is not sorted");
}
#endif
uint64_t Bits = 0; // Resulting bits
// Resulting bits
FeatureBitset Bits;
// Check if help is needed
if (CPU == "help")
@@ -247,7 +248,7 @@ SubtargetFeatures::getFeatureBits(StringRef CPU,
// Set the feature implied by this CPU feature, if any.
for (auto &FE : FeatureTable) {
if (CPUEntry->Value & FE.Value)
if ((CPUEntry->Value & FE.Value).any())
SetImpliedBits(Bits, &FE, FeatureTable);
}
} else {