Mercurial > hg > truffle

changeset 6518:ea845fd3c820

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
add hashCode fast path for System.identityHashCode
author Lukas Stadler <lukas.stadler@jku.at>
date Fri, 05 Oct 2012 15:17:27 +0200
parents 2dfab5607b3d
children feabae0d6bdc
files src/cpu/x86/vm/sharedRuntime_x86_64.cpp
diffstat 1 files changed, 13 insertions(+), 1 deletions(-) [+]
line wrap: on
line diff
--- a/src/cpu/x86/vm/sharedRuntime_x86_64.cpp	Fri Oct 05 13:44:26 2012 +0200
+++ b/src/cpu/x86/vm/sharedRuntime_x86_64.cpp	Fri Oct 05 15:17:27 2012 +0200
@@ -1970,14 +1970,20 @@
   int vep_offset = ((intptr_t)__ pc()) - start;
 
 #ifdef GRAAL
-  if (InlineObjectHash && method->intrinsic_id() == vmIntrinsics::_hashCode) {
+  if (InlineObjectHash && (method->intrinsic_id() == vmIntrinsics::_hashCode || method->intrinsic_id() == vmIntrinsics::_identityHashCode)) {
     // Object.hashCode can pull the hashCode from the header word
     // instead of doing a full VM transition once it's been computed.
     // Since hashCode is usually polymorphic at call sites we can't do
     // this optimization at the call site without a lot of work.
     Label slowCase;
+    Label nullCase;
     Register result = rax;
 
+    if (method->intrinsic_id() == vmIntrinsics::_identityHashCode) {
+      __ cmpptr(receiver, 0);
+      __ jcc(Assembler::equal, nullCase);
+    }
+
     __ movptr(result, Address(receiver, oopDesc::mark_offset_in_bytes()));
 
     // check if locked
@@ -1997,6 +2003,12 @@
     __ jcc  (Assembler::zero, slowCase);
     __ ret(0);
 
+    if (method->intrinsic_id() == vmIntrinsics::_identityHashCode) {
+      __ bind(nullCase);
+      __ movl(result, 0);
+      __ ret(0);
+    }
+
     __ bind (slowCase);
   }
 #endif // GRAAL