ARM/ARM64: Implement numberOfLeadingZeros intrinsic.
Change-Id: I4042fb7a0b75140475dcfca23e8f79d310f5333b
diff --git a/compiler/optimizing/intrinsics_arm.cc b/compiler/optimizing/intrinsics_arm.cc
index b4dbf75..a797654 100644
--- a/compiler/optimizing/intrinsics_arm.cc
+++ b/compiler/optimizing/intrinsics_arm.cc
@@ -224,6 +224,48 @@
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
}
+static void GenNumberOfLeadingZeros(LocationSummary* locations,
+ Primitive::Type type,
+ ArmAssembler* assembler) {
+ Location in = locations->InAt(0);
+ Register out = locations->Out().AsRegister<Register>();
+
+ DCHECK((type == Primitive::kPrimInt) || (type == Primitive::kPrimLong));
+
+ if (type == Primitive::kPrimLong) {
+ Register in_reg_lo = in.AsRegisterPairLow<Register>();
+ Register in_reg_hi = in.AsRegisterPairHigh<Register>();
+ Label end;
+ __ clz(out, in_reg_hi);
+ __ CompareAndBranchIfNonZero(in_reg_hi, &end);
+ __ clz(out, in_reg_lo);
+ __ AddConstant(out, 32);
+ __ Bind(&end);
+ } else {
+ __ clz(out, in.AsRegister<Register>());
+ }
+}
+
+void IntrinsicLocationsBuilderARM::VisitIntegerNumberOfLeadingZeros(HInvoke* invoke) {
+ CreateIntToIntLocations(arena_, invoke);
+}
+
+void IntrinsicCodeGeneratorARM::VisitIntegerNumberOfLeadingZeros(HInvoke* invoke) {
+ GenNumberOfLeadingZeros(invoke->GetLocations(), Primitive::kPrimInt, GetAssembler());
+}
+
+void IntrinsicLocationsBuilderARM::VisitLongNumberOfLeadingZeros(HInvoke* invoke) {
+ LocationSummary* locations = new (arena_) LocationSummary(invoke,
+ LocationSummary::kNoCall,
+ kIntrinsified);
+ locations->SetInAt(0, Location::RequiresRegister());
+ locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
+}
+
+void IntrinsicCodeGeneratorARM::VisitLongNumberOfLeadingZeros(HInvoke* invoke) {
+ GenNumberOfLeadingZeros(invoke->GetLocations(), Primitive::kPrimLong, GetAssembler());
+}
+
static void MathAbsFP(LocationSummary* locations, bool is64bit, ArmAssembler* assembler) {
Location in = locations->InAt(0);
Location out = locations->Out();