Changeset 226616 in webkit

Timestamp:

Jan 8, 2018 11:17:06 PM (6 years ago)

Author:

zandobersek@gmail.com

Message:

REGRESSION(r225913): about 30 JSC test failures on ARMv7
​https://bugs.webkit.org/show_bug.cgi?id=181162
<rdar://problem/36261349>

Unreviewed follow-up to r226298. Enable the fast case in
DFG::SpeculativeJIT::compileArraySlice() for any 64-bit platform,
assuming in good faith that enough GP registers are available on any
such configuration. The accompanying comment is adjusted to describe
this assumption.

• dfg/DFGSpeculativeJIT.cpp:

(JSC::DFG::SpeculativeJIT::compileArraySlice):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• dfg/DFGSpeculativeJIT.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2018-01-08  Zan Dobersek  <zdobersek@igalia.com>
+
+        REGRESSION(r225913): about 30 JSC test failures on ARMv7
+        https://bugs.webkit.org/show_bug.cgi?id=181162
+        <rdar://problem/36261349>
+
+        Unreviewed follow-up to r226298. Enable the fast case in
+        DFG::SpeculativeJIT::compileArraySlice() for any 64-bit platform,
+        assuming in good faith that enough GP registers are available on any
+        such configuration. The accompanying comment is adjusted to describe
+        this assumption.
+
+        * dfg/DFGSpeculativeJIT.cpp:
+        (JSC::DFG::SpeculativeJIT::compileArraySlice):
+
 2018-01-08  JF Bastien  <jfbastien@apple.com>
 

trunk/Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp

@@ -7640 +7640 @@
         MacroAssembler::JumpList slowCases;
         m_jit.move(TrustedImmPtr(0), storageResultGPR);
-        // X86 only has 6 GP registers, which is not enough for the fast case here. At least without custom code, which is not currently worth the extra code maintenance.
-        if (isARM64() || isX86_64()) {
+        // Enable the fast case on 64-bit platforms, where a sufficient amount of GP registers should be available.
+        // Other platforms could support the same approach with custom code, but that is not currently worth the extra code maintenance.
+        if (is64Bit()) {
             GPRTemporary scratch(this);
             GPRTemporary scratch2(this);