Mercurial > hg > truffle
view src/cpu/x86/vm/jniFastGetField_x86_64.cpp @ 10185:d50cc62e94ff
8012715: G1: GraphKit accesses PtrQueue::_index as int but is size_t
Summary: In graphKit INT operations were generated to access PtrQueue::_index which has type size_t. This is 64 bit on 64-bit machines. No problems occur on little endian machines as long as the index fits into 32 bit, but on big endian machines the upper part is read, which is zero. This leads to unnecessary branches to the slow path in the runtime.
Reviewed-by: twisti, johnc
Contributed-by: Martin Doerr <martin.doerr@sap.com>
author | johnc |
---|---|
date | Wed, 24 Apr 2013 14:48:43 -0700 |
parents | cd3d6a6b95d9 |
children |
line wrap: on
line source
/* * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "asm/macroAssembler.hpp" #include "memory/resourceArea.hpp" #include "prims/jniFastGetField.hpp" #include "prims/jvm_misc.hpp" #include "runtime/safepoint.hpp" #define __ masm-> #define BUFFER_SIZE 30*wordSize // Instead of issuing lfence for LoadLoad barrier, we create data dependency // between loads, which is more efficient than lfence. // Common register usage: // rax/xmm0: result // c_rarg0: jni env // c_rarg1: obj // c_rarg2: jfield id static const Register robj = r9; static const Register rcounter = r10; static const Register roffset = r11; static const Register rcounter_addr = r11; // Warning: do not use rip relative addressing after the first counter load // since that may scratch r10! address JNI_FastGetField::generate_fast_get_int_field0(BasicType type) { const char *name; switch (type) { case T_BOOLEAN: name = "jni_fast_GetBooleanField"; break; case T_BYTE: name = "jni_fast_GetByteField"; break; case T_CHAR: name = "jni_fast_GetCharField"; break; case T_SHORT: name = "jni_fast_GetShortField"; break; case T_INT: name = "jni_fast_GetIntField"; break; case T_LONG: name = "jni_fast_GetLongField"; break; default: ShouldNotReachHere(); } ResourceMark rm; BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE); CodeBuffer cbuf(blob); MacroAssembler* masm = new MacroAssembler(&cbuf); address fast_entry = __ pc(); Label slow; ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr()); __ mov32 (rcounter, counter); __ mov (robj, c_rarg1); __ testb (rcounter, 1); __ jcc (Assembler::notZero, slow); if (os::is_MP()) { __ xorptr(robj, rcounter); __ xorptr(robj, rcounter); // obj, since // robj ^ rcounter ^ rcounter == robj // robj is data dependent on rcounter. } __ movptr(robj, Address(robj, 0)); // *obj __ mov (roffset, c_rarg2); __ shrptr(roffset, 2); // offset assert(count < LIST_CAPACITY, "LIST_CAPACITY too small"); speculative_load_pclist[count] = __ pc(); switch (type) { case T_BOOLEAN: __ movzbl (rax, Address(robj, roffset, Address::times_1)); break; case T_BYTE: __ movsbl (rax, Address(robj, roffset, Address::times_1)); break; case T_CHAR: __ movzwl (rax, Address(robj, roffset, Address::times_1)); break; case T_SHORT: __ movswl (rax, Address(robj, roffset, Address::times_1)); break; case T_INT: __ movl (rax, Address(robj, roffset, Address::times_1)); break; case T_LONG: __ movq (rax, Address(robj, roffset, Address::times_1)); break; default: ShouldNotReachHere(); } if (os::is_MP()) { __ lea(rcounter_addr, counter); // ca is data dependent on rax. __ xorptr(rcounter_addr, rax); __ xorptr(rcounter_addr, rax); __ cmpl (rcounter, Address(rcounter_addr, 0)); } else { __ cmp32 (rcounter, counter); } __ jcc (Assembler::notEqual, slow); __ ret (0); slowcase_entry_pclist[count++] = __ pc(); __ bind (slow); address slow_case_addr; switch (type) { case T_BOOLEAN: slow_case_addr = jni_GetBooleanField_addr(); break; case T_BYTE: slow_case_addr = jni_GetByteField_addr(); break; case T_CHAR: slow_case_addr = jni_GetCharField_addr(); break; case T_SHORT: slow_case_addr = jni_GetShortField_addr(); break; case T_INT: slow_case_addr = jni_GetIntField_addr(); break; case T_LONG: slow_case_addr = jni_GetLongField_addr(); } // tail call __ jump (ExternalAddress(slow_case_addr)); __ flush (); return fast_entry; } address JNI_FastGetField::generate_fast_get_boolean_field() { return generate_fast_get_int_field0(T_BOOLEAN); } address JNI_FastGetField::generate_fast_get_byte_field() { return generate_fast_get_int_field0(T_BYTE); } address JNI_FastGetField::generate_fast_get_char_field() { return generate_fast_get_int_field0(T_CHAR); } address JNI_FastGetField::generate_fast_get_short_field() { return generate_fast_get_int_field0(T_SHORT); } address JNI_FastGetField::generate_fast_get_int_field() { return generate_fast_get_int_field0(T_INT); } address JNI_FastGetField::generate_fast_get_long_field() { return generate_fast_get_int_field0(T_LONG); } address JNI_FastGetField::generate_fast_get_float_field0(BasicType type) { const char *name; switch (type) { case T_FLOAT: name = "jni_fast_GetFloatField"; break; case T_DOUBLE: name = "jni_fast_GetDoubleField"; break; default: ShouldNotReachHere(); } ResourceMark rm; BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE); CodeBuffer cbuf(blob); MacroAssembler* masm = new MacroAssembler(&cbuf); address fast_entry = __ pc(); Label slow; ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr()); __ mov32 (rcounter, counter); __ mov (robj, c_rarg1); __ testb (rcounter, 1); __ jcc (Assembler::notZero, slow); if (os::is_MP()) { __ xorptr(robj, rcounter); __ xorptr(robj, rcounter); // obj, since // robj ^ rcounter ^ rcounter == robj // robj is data dependent on rcounter. } __ movptr(robj, Address(robj, 0)); // *obj __ mov (roffset, c_rarg2); __ shrptr(roffset, 2); // offset assert(count < LIST_CAPACITY, "LIST_CAPACITY too small"); speculative_load_pclist[count] = __ pc(); switch (type) { case T_FLOAT: __ movflt (xmm0, Address(robj, roffset, Address::times_1)); break; case T_DOUBLE: __ movdbl (xmm0, Address(robj, roffset, Address::times_1)); break; default: ShouldNotReachHere(); } if (os::is_MP()) { __ lea(rcounter_addr, counter); __ movdq (rax, xmm0); // counter address is data dependent on xmm0. __ xorptr(rcounter_addr, rax); __ xorptr(rcounter_addr, rax); __ cmpl (rcounter, Address(rcounter_addr, 0)); } else { __ cmp32 (rcounter, counter); } __ jcc (Assembler::notEqual, slow); __ ret (0); slowcase_entry_pclist[count++] = __ pc(); __ bind (slow); address slow_case_addr; switch (type) { case T_FLOAT: slow_case_addr = jni_GetFloatField_addr(); break; case T_DOUBLE: slow_case_addr = jni_GetDoubleField_addr(); } // tail call __ jump (ExternalAddress(slow_case_addr)); __ flush (); return fast_entry; } address JNI_FastGetField::generate_fast_get_float_field() { return generate_fast_get_float_field0(T_FLOAT); } address JNI_FastGetField::generate_fast_get_double_field() { return generate_fast_get_float_field0(T_DOUBLE); }