Modified: trunk/Source/_javascript_Core/ChangeLog (199864 => 199865)
--- trunk/Source/_javascript_Core/ChangeLog 2016-04-22 04:26:09 UTC (rev 199864)
+++ trunk/Source/_javascript_Core/ChangeLog 2016-04-22 04:29:02 UTC (rev 199865)
@@ -1,3 +1,21 @@
+2016-04-21 Benjamin Poulain <benja...@webkit.org>
+
+ [JSC] Improve the absThunkGenerator() for 64bit
+ https://bugs.webkit.org/show_bug.cgi?id=156888
+
+ Reviewed by Michael Saboff.
+
+ A few tests spend a lot of time in this abs() with double argument.
+
+ This patch adds custom handling for the JSValue64 representation.
+ In particular:
+ -Do not load the value twice. Unbox the GPR if it is not an Int32.
+ -Deal with IntMin inline instead of falling back to the C function call.
+ -Box the values ourself to avoid a duplicate function tail and return.
+
+ * jit/ThunkGenerators.cpp:
+ (JSC::absThunkGenerator):
+
2016-04-21 Saam barati <sbar...@apple.com>
LLInt CallSiteIndex off by 1
Modified: trunk/Source/_javascript_Core/jit/ThunkGenerators.cpp (199864 => 199865)
--- trunk/Source/_javascript_Core/jit/ThunkGenerators.cpp 2016-04-22 04:26:09 UTC (rev 199864)
+++ trunk/Source/_javascript_Core/jit/ThunkGenerators.cpp 2016-04-22 04:29:02 UTC (rev 199865)
@@ -928,6 +928,42 @@
SpecializedThunkJIT jit(vm, 1);
if (!jit.supportsFloatingPointAbs())
return MacroAssemblerCodeRef::createSelfManagedCodeRef(vm->jitStubs->ctiNativeCall(vm));
+
+#if USE(JSVALUE64)
+ unsigned virtualRegisterIndex = CallFrame::argumentOffset(0);
+ jit.load64(AssemblyHelpers::addressFor(virtualRegisterIndex), GPRInfo::regT0);
+ MacroAssembler::Jump notInteger = jit.branch64(MacroAssembler::Below, GPRInfo::regT0, GPRInfo::tagTypeNumberRegister);
+
+ // Abs Int32.
+ jit.rshift32(GPRInfo::regT0, MacroAssembler::TrustedImm32(31), GPRInfo::regT1);
+ jit.add32(GPRInfo::regT1, GPRInfo::regT0);
+ jit.xor32(GPRInfo::regT1, GPRInfo::regT0);
+
+ // IntMin cannot be inverted.
+ MacroAssembler::Jump integerIsIntMin = jit.branchTest32(MacroAssembler::Signed, GPRInfo::regT0);
+
+ // Box and finish.
+ jit.or64(GPRInfo::tagTypeNumberRegister, GPRInfo::regT0);
+ MacroAssembler::Jump doneWithIntegers = jit.jump();
+
+ // Handle Doubles.
+ notInteger.link(&jit);
+ jit.appendFailure(jit.branchTest64(MacroAssembler::Zero, GPRInfo::regT0, GPRInfo::tagTypeNumberRegister));
+ jit.unboxDoubleWithoutAssertions(GPRInfo::regT0, GPRInfo::regT0, FPRInfo::fpRegT0);
+ MacroAssembler::Label absFPR0Label = jit.label();
+ jit.absDouble(FPRInfo::fpRegT0, FPRInfo::fpRegT1);
+ jit.boxDouble(FPRInfo::fpRegT1, GPRInfo::regT0);
+
+ // Tail.
+ doneWithIntegers.link(&jit);
+ jit.returnJSValue(GPRInfo::regT0);
+
+ // We know the value of regT0 is IntMin. We could load that value from memory but
+ // it is simpler to just convert it.
+ integerIsIntMin.link(&jit);
+ jit.convertInt32ToDouble(GPRInfo::regT0, FPRInfo::fpRegT0);
+ jit.jump().linkTo(absFPR0Label, &jit);
+#else
MacroAssembler::Jump nonIntJump;
jit.loadInt32Argument(0, SpecializedThunkJIT::regT0, nonIntJump);
jit.rshift32(SpecializedThunkJIT::regT0, MacroAssembler::TrustedImm32(31), SpecializedThunkJIT::regT1);
@@ -940,6 +976,7 @@
jit.loadDoubleArgument(0, SpecializedThunkJIT::fpRegT0, SpecializedThunkJIT::regT0);
jit.absDouble(SpecializedThunkJIT::fpRegT0, SpecializedThunkJIT::fpRegT1);
jit.returnDouble(SpecializedThunkJIT::fpRegT1);
+#endif
return jit.finalize(vm->jitStubs->ctiNativeTailCall(vm), "abs");
}
