Changeset 291217 in webkit for trunk/Source/JavaScriptCore/assembler/MacroAssemblerMIPS.h

Timestamp:

Mar 13, 2022, 7:34:17 AM (3 years ago)

Author:

Angelos Oikonomopoulos

Message:

[JSC] Use addressTempRegister in loadValue(void *) on 32 bits
​https://bugs.webkit.org/show_bug.cgi?id=237773

Reviewed by Žan Doberšek.

Instead of using one of the destination registers as an address
temporary, use addressTempRegister instead. This allows reusing
the value in addressTempRegister (with an appropriate offset) if
possible, which results in a >25% size reduction for DFGOSRExit
(JS2) on ARMv7 (though not a significant size reduction overall).
Technically, this change could be killing some address reuse that
was previously possible because loadValue was not clobbering
addressTempRegister but, if so, this seems to be balanced out for
JS2.

• assembler/MacroAssemblerARMv7.h:

(JSC::MacroAssemblerARMv7::BoundsNonDoubleWordOffset::within):
(JSC::MacroAssemblerARMv7::BoundsDoubleWordOffset::within):
(JSC::MacroAssemblerARMv7::loadPair32):
(JSC::MacroAssemblerARMv7::setupArmAddress):
(JSC::MacroAssemblerARMv7::absoluteAddressWithinShortOffset):

• assembler/MacroAssemblerMIPS.h:

(JSC::MacroAssemblerMIPS::loadPair32):

• jit/AssemblyHelpers.h:

(JSC::AssemblyHelpers::loadValue):

File:

• trunk/Source/JavaScriptCore/assembler/MacroAssemblerMIPS.h (modified) (1 diff)

trunk/Source/JavaScriptCore/assembler/MacroAssemblerMIPS.h

@@ -1335 +1335 @@
             load32(address.withOffset(4), dest2);
         }
+    }
+
+    void loadPair32(AbsoluteAddress address, RegisterID dest1, RegisterID dest2)
+    {
+        move(TrustedImmPtr(address.m_ptr), addrTempRegister);
+        loadPair32(addrTempRegister, dest1, dest2);
     }