view src/os_cpu/bsd_x86/vm/bsd_x86_64.s @ 20543:e7d0505c8a30

8059758: Footprint regressions with JDK-8038423 Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything. Reviewed-by: jwilhelm, brutisso
author tschatzl
date Fri, 10 Oct 2014 15:51:58 +0200
parents 55fb97c4c58d
children 4ca6dc0799b6
line wrap: on
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# 
# Copyright (c) 2004, 2013, 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.
#

#ifdef __APPLE__
# Darwin uses _ prefixed global symbols
#define SYMBOL(s) _ ## s
#define ELF_TYPE(name, description)
#else
#define SYMBOL(s) s
#define ELF_TYPE(name, description) .type name,description
#endif

        # NOTE WELL!  The _Copy functions are called directly
	# from server-compiler-generated code via CallLeafNoFP,
	# which means that they *must* either not use floating
	# point or use it in the same manner as does the server
	# compiler.
	
        .globl SYMBOL(_Copy_arrayof_conjoint_bytes)
	.globl SYMBOL(_Copy_arrayof_conjoint_jshorts)
        .globl SYMBOL(_Copy_conjoint_jshorts_atomic)
        .globl SYMBOL(_Copy_arrayof_conjoint_jints)
        .globl SYMBOL(_Copy_conjoint_jints_atomic)
        .globl SYMBOL(_Copy_arrayof_conjoint_jlongs)
        .globl SYMBOL(_Copy_conjoint_jlongs_atomic)

	.text

        .globl SYMBOL(SpinPause)
        .p2align 4,,15
        ELF_TYPE(SpinPause,@function)
SYMBOL(SpinPause):
        rep
        nop
        movq   $1, %rax
        ret

        # Support for void Copy::arrayof_conjoint_bytes(void* from,
        #                                               void* to,
        #                                               size_t count)
        # rdi - from
        # rsi - to
        # rdx - count, treated as ssize_t
        #
        .p2align 4,,15
	ELF_TYPE(_Copy_arrayof_conjoint_bytes,@function)
SYMBOL(_Copy_arrayof_conjoint_bytes):
        movq     %rdx,%r8             # byte count
        shrq     $3,%rdx              # qword count
        cmpq     %rdi,%rsi
        leaq     -1(%rdi,%r8,1),%rax  # from + bcount*1 - 1
        jbe      acb_CopyRight
        cmpq     %rax,%rsi
        jbe      acb_CopyLeft 
acb_CopyRight:
        leaq     -8(%rdi,%rdx,8),%rax # from + qcount*8 - 8
        leaq     -8(%rsi,%rdx,8),%rcx # to + qcount*8 - 8
        negq     %rdx
        jmp      7f
        .p2align 4,,15
1:      movq     8(%rax,%rdx,8),%rsi
        movq     %rsi,8(%rcx,%rdx,8)
        addq     $1,%rdx
        jnz      1b
2:      testq    $4,%r8               # check for trailing dword
        jz       3f
        movl     8(%rax),%esi         # copy trailing dword
        movl     %esi,8(%rcx)
        addq     $4,%rax
        addq     $4,%rcx              # original %rsi is trashed, so we
                                      #  can't use it as a base register
3:      testq    $2,%r8               # check for trailing word
        jz       4f
        movw     8(%rax),%si          # copy trailing word
        movw     %si,8(%rcx)
        addq     $2,%rcx
4:      testq    $1,%r8               # check for trailing byte
        jz       5f
        movb     -1(%rdi,%r8,1),%al   # copy trailing byte
        movb     %al,8(%rcx)
5:      ret
        .p2align 4,,15
6:      movq     -24(%rax,%rdx,8),%rsi
        movq     %rsi,-24(%rcx,%rdx,8)
        movq     -16(%rax,%rdx,8),%rsi
        movq     %rsi,-16(%rcx,%rdx,8)
        movq     -8(%rax,%rdx,8),%rsi
        movq     %rsi,-8(%rcx,%rdx,8)
        movq     (%rax,%rdx,8),%rsi
        movq     %rsi,(%rcx,%rdx,8)
7:      addq     $4,%rdx
        jle      6b
        subq     $4,%rdx
        jl       1b
        jmp      2b
acb_CopyLeft:
        testq    $1,%r8               # check for trailing byte
        jz       1f
        movb     -1(%rdi,%r8,1),%cl   # copy trailing byte
        movb     %cl,-1(%rsi,%r8,1)
        subq     $1,%r8               # adjust for possible trailing word
1:      testq    $2,%r8               # check for trailing word
        jz       2f
        movw     -2(%rdi,%r8,1),%cx   # copy trailing word
        movw     %cx,-2(%rsi,%r8,1)
2:      testq    $4,%r8               # check for trailing dword
        jz       5f
        movl     (%rdi,%rdx,8),%ecx   # copy trailing dword
        movl     %ecx,(%rsi,%rdx,8)
        jmp      5f
        .p2align 4,,15
3:      movq     -8(%rdi,%rdx,8),%rcx
        movq     %rcx,-8(%rsi,%rdx,8)
        subq     $1,%rdx
        jnz      3b
        ret
        .p2align 4,,15
4:      movq     24(%rdi,%rdx,8),%rcx
        movq     %rcx,24(%rsi,%rdx,8)
        movq     16(%rdi,%rdx,8),%rcx
        movq     %rcx,16(%rsi,%rdx,8)
        movq     8(%rdi,%rdx,8),%rcx
        movq     %rcx,8(%rsi,%rdx,8)
        movq     (%rdi,%rdx,8),%rcx
        movq     %rcx,(%rsi,%rdx,8)
5:      subq     $4,%rdx
        jge      4b
        addq     $4,%rdx
        jg       3b
        ret

        # Support for void Copy::arrayof_conjoint_jshorts(void* from,
        #                                                 void* to,
        #                                                 size_t count)
        # Equivalent to
        #   conjoint_jshorts_atomic
        #
        # If 'from' and/or 'to' are aligned on 4- or 2-byte boundaries, we
        # let the hardware handle it.  The tow or four words within dwords
        # or qwords that span cache line boundaries will still be loaded
        # and stored atomically.
        #
        # rdi - from
        # rsi - to
        # rdx - count, treated as ssize_t
        #
        .p2align 4,,15
	ELF_TYPE(_Copy_arrayof_conjoint_jshorts,@function)
	ELF_TYPE(_Copy_conjoint_jshorts_atomic,@function)
SYMBOL(_Copy_arrayof_conjoint_jshorts):
SYMBOL(_Copy_conjoint_jshorts_atomic):
        movq     %rdx,%r8             # word count
        shrq     $2,%rdx              # qword count
        cmpq     %rdi,%rsi
        leaq     -2(%rdi,%r8,2),%rax  # from + wcount*2 - 2
        jbe      acs_CopyRight
        cmpq     %rax,%rsi
        jbe      acs_CopyLeft 
acs_CopyRight:
        leaq     -8(%rdi,%rdx,8),%rax # from + qcount*8 - 8
        leaq     -8(%rsi,%rdx,8),%rcx # to + qcount*8 - 8
        negq     %rdx
        jmp      6f
1:      movq     8(%rax,%rdx,8),%rsi
        movq     %rsi,8(%rcx,%rdx,8)
        addq     $1,%rdx
        jnz      1b
2:      testq    $2,%r8               # check for trailing dword
        jz       3f
        movl     8(%rax),%esi         # copy trailing dword
        movl     %esi,8(%rcx)
        addq     $4,%rcx              # original %rsi is trashed, so we
                                      #  can't use it as a base register
3:      testq    $1,%r8               # check for trailing word
        jz       4f
        movw     -2(%rdi,%r8,2),%si   # copy trailing word
        movw     %si,8(%rcx)
4:      ret
        .p2align 4,,15
5:      movq     -24(%rax,%rdx,8),%rsi
        movq     %rsi,-24(%rcx,%rdx,8)
        movq     -16(%rax,%rdx,8),%rsi
        movq     %rsi,-16(%rcx,%rdx,8)
        movq     -8(%rax,%rdx,8),%rsi
        movq     %rsi,-8(%rcx,%rdx,8)
        movq     (%rax,%rdx,8),%rsi
        movq     %rsi,(%rcx,%rdx,8)
6:      addq     $4,%rdx
        jle      5b
        subq     $4,%rdx
        jl       1b
        jmp      2b
acs_CopyLeft:
        testq    $1,%r8               # check for trailing word
        jz       1f
        movw     -2(%rdi,%r8,2),%cx   # copy trailing word
        movw     %cx,-2(%rsi,%r8,2)
1:      testq    $2,%r8               # check for trailing dword
        jz       4f
        movl     (%rdi,%rdx,8),%ecx   # copy trailing dword
        movl     %ecx,(%rsi,%rdx,8)
        jmp      4f
2:      movq     -8(%rdi,%rdx,8),%rcx
        movq     %rcx,-8(%rsi,%rdx,8)
        subq     $1,%rdx
        jnz      2b
        ret
        .p2align 4,,15
3:      movq     24(%rdi,%rdx,8),%rcx
        movq     %rcx,24(%rsi,%rdx,8)
        movq     16(%rdi,%rdx,8),%rcx
        movq     %rcx,16(%rsi,%rdx,8)
        movq     8(%rdi,%rdx,8),%rcx
        movq     %rcx,8(%rsi,%rdx,8)
        movq     (%rdi,%rdx,8),%rcx
        movq     %rcx,(%rsi,%rdx,8)
4:      subq     $4,%rdx
        jge      3b
        addq     $4,%rdx
        jg       2b
        ret

        # Support for void Copy::arrayof_conjoint_jints(jint* from,
        #                                               jint* to,
        #                                               size_t count)
        # Equivalent to
        #   conjoint_jints_atomic
        #
        # If 'from' and/or 'to' are aligned on 4-byte boundaries, we let
        # the hardware handle it.  The two dwords within qwords that span
        # cache line boundaries will still be loaded and stored atomically.
        #
        # rdi - from
        # rsi - to
        # rdx - count, treated as ssize_t
        #
        .p2align 4,,15
	ELF_TYPE(_Copy_arrayof_conjoint_jints,@function)
	ELF_TYPE(_Copy_conjoint_jints_atomic,@function)
SYMBOL(_Copy_arrayof_conjoint_jints):
SYMBOL(_Copy_conjoint_jints_atomic):
        movq     %rdx,%r8             # dword count
        shrq     %rdx                 # qword count
        cmpq     %rdi,%rsi
        leaq     -4(%rdi,%r8,4),%rax  # from + dcount*4 - 4
        jbe      aci_CopyRight
        cmpq     %rax,%rsi
        jbe      aci_CopyLeft 
aci_CopyRight:
        leaq     -8(%rdi,%rdx,8),%rax # from + qcount*8 - 8
        leaq     -8(%rsi,%rdx,8),%rcx # to + qcount*8 - 8
        negq     %rdx
        jmp      5f
        .p2align 4,,15
1:      movq     8(%rax,%rdx,8),%rsi
        movq     %rsi,8(%rcx,%rdx,8)
        addq     $1,%rdx
        jnz       1b
2:      testq    $1,%r8               # check for trailing dword
        jz       3f
        movl     8(%rax),%esi         # copy trailing dword
        movl     %esi,8(%rcx)
3:      ret
        .p2align 4,,15
4:      movq     -24(%rax,%rdx,8),%rsi
        movq     %rsi,-24(%rcx,%rdx,8)
        movq     -16(%rax,%rdx,8),%rsi
        movq     %rsi,-16(%rcx,%rdx,8)
        movq     -8(%rax,%rdx,8),%rsi
        movq     %rsi,-8(%rcx,%rdx,8)
        movq     (%rax,%rdx,8),%rsi
        movq     %rsi,(%rcx,%rdx,8)
5:      addq     $4,%rdx
        jle      4b
        subq     $4,%rdx
        jl       1b
        jmp      2b
aci_CopyLeft:
        testq    $1,%r8               # check for trailing dword
        jz       3f
        movl     -4(%rdi,%r8,4),%ecx  # copy trailing dword
        movl     %ecx,-4(%rsi,%r8,4)
        jmp      3f
1:      movq     -8(%rdi,%rdx,8),%rcx
        movq     %rcx,-8(%rsi,%rdx,8)
        subq     $1,%rdx
        jnz      1b
        ret
        .p2align 4,,15
2:      movq     24(%rdi,%rdx,8),%rcx
        movq     %rcx,24(%rsi,%rdx,8)
        movq     16(%rdi,%rdx,8),%rcx
        movq     %rcx,16(%rsi,%rdx,8)
        movq     8(%rdi,%rdx,8),%rcx
        movq     %rcx,8(%rsi,%rdx,8)
        movq     (%rdi,%rdx,8),%rcx
        movq     %rcx,(%rsi,%rdx,8)
3:      subq     $4,%rdx
        jge      2b
        addq     $4,%rdx
        jg       1b
        ret

        # Support for void Copy::arrayof_conjoint_jlongs(jlong* from,
        #                                                jlong* to,
        #                                                size_t count)
        # Equivalent to
        #   conjoint_jlongs_atomic
        #   arrayof_conjoint_oops
        #   conjoint_oops_atomic
        #
        # rdi - from
        # rsi - to
        # rdx - count, treated as ssize_t
        #
        .p2align 4,,15
	ELF_TYPE(_Copy_arrayof_conjoint_jlongs,@function)
	ELF_TYPE(_Copy_conjoint_jlongs_atomic,@function)
SYMBOL(_Copy_arrayof_conjoint_jlongs):
SYMBOL(_Copy_conjoint_jlongs_atomic):
        cmpq     %rdi,%rsi
        leaq     -8(%rdi,%rdx,8),%rax # from + count*8 - 8
        jbe      acl_CopyRight
        cmpq     %rax,%rsi
        jbe      acl_CopyLeft 
acl_CopyRight:
        leaq     -8(%rsi,%rdx,8),%rcx # to + count*8 - 8
        negq     %rdx
        jmp      3f
1:      movq     8(%rax,%rdx,8),%rsi
        movq     %rsi,8(%rcx,%rdx,8)
        addq     $1,%rdx
        jnz      1b
        ret
        .p2align 4,,15
2:      movq     -24(%rax,%rdx,8),%rsi
        movq     %rsi,-24(%rcx,%rdx,8)
        movq     -16(%rax,%rdx,8),%rsi
        movq     %rsi,-16(%rcx,%rdx,8)
        movq     -8(%rax,%rdx,8),%rsi
        movq     %rsi,-8(%rcx,%rdx,8)
        movq     (%rax,%rdx,8),%rsi
        movq     %rsi,(%rcx,%rdx,8)
3:      addq     $4,%rdx
        jle      2b
        subq     $4,%rdx
        jl       1b
        ret
4:      movq     -8(%rdi,%rdx,8),%rcx
        movq     %rcx,-8(%rsi,%rdx,8)
        subq     $1,%rdx
        jnz      4b
        ret
        .p2align 4,,15
5:      movq     24(%rdi,%rdx,8),%rcx
        movq     %rcx,24(%rsi,%rdx,8)
        movq     16(%rdi,%rdx,8),%rcx
        movq     %rcx,16(%rsi,%rdx,8)
        movq     8(%rdi,%rdx,8),%rcx
        movq     %rcx,8(%rsi,%rdx,8)
        movq     (%rdi,%rdx,8),%rcx
        movq     %rcx,(%rsi,%rdx,8)
acl_CopyLeft:
        subq     $4,%rdx
        jge      5b
        addq     $4,%rdx
        jg       4b
        ret