diff options
Diffstat (limited to 'gcc/config/i386/cygwin.asm')
| -rw-r--r-- | gcc/config/i386/cygwin.asm | 214 |
1 files changed, 138 insertions, 76 deletions
diff --git a/gcc/config/i386/cygwin.asm b/gcc/config/i386/cygwin.asm index 588c12ee701..a6cc94d160a 100644 --- a/gcc/config/i386/cygwin.asm +++ b/gcc/config/i386/cygwin.asm @@ -1,6 +1,7 @@ /* stuff needed for libgcc on win32. * - * Copyright (C) 1996, 1998, 2001, 2003, 2008, 2009 Free Software Foundation, Inc. + * Copyright (C) 1996, 1998, 2001, 2003, 2008, 2009 + * Free Software Foundation, Inc. * Written By Steve Chamberlain * * This file is free software; you can redistribute it and/or modify it @@ -23,104 +24,165 @@ * <http://www.gnu.org/licenses/>. */ -#ifdef L_chkstk +#include "auto-host.h" + +#ifdef HAVE_GAS_CFI_SECTIONS_DIRECTIVE + .cfi_sections .debug_frame +# define cfi_startproc() .cfi_startproc +# define cfi_endproc() .cfi_endproc +# define cfi_adjust_cfa_offset(X) .cfi_adjust_cfa_offset X +# define cfi_def_cfa_register(X) .cfi_def_cfa_register X +# define cfi_register(D,S) .cfi_register D, S +# ifdef _WIN64 +# define cfi_push(X) .cfi_adjust_cfa_offset 8; .cfi_rel_offset X, 0 +# define cfi_pop(X) .cfi_adjust_cfa_offset -8; .cfi_restore X +# else +# define cfi_push(X) .cfi_adjust_cfa_offset 4; .cfi_rel_offset X, 0 +# define cfi_pop(X) .cfi_adjust_cfa_offset -4; .cfi_restore X +# endif +#else +# define cfi_startproc() +# define cfi_endproc() +# define cfi_adjust_cfa_offset(X) +# define cfi_def_cfa_register(X) +# define cfi_register(D,S) +# define cfi_push(X) +# define cfi_pop(X) +#endif /* HAVE_GAS_CFI_SECTIONS_DIRECTIVE */ -/* Function prologue calls _alloca to probe the stack when allocating more +#ifdef L_chkstk +/* Function prologue calls __chkstk to probe the stack when allocating more than CHECK_STACK_LIMIT bytes in one go. Touching the stack at 4K increments is necessary to ensure that the guard pages used by the OS virtual memory manger are allocated in correct sequence. */ .global ___chkstk .global __alloca -#ifndef _WIN64 -___chkstk: +#ifdef _WIN64 +/* __alloca is a normal function call, which uses %rcx as the argument. */ + cfi_startproc() __alloca: - pushl %ecx /* save temp */ - leal 8(%esp), %ecx /* point past return addr */ - cmpl $0x1000, %eax /* > 4k ?*/ - jb Ldone + movq %rcx, %rax + /* FALLTHRU */ -Lprobe: - subl $0x1000, %ecx /* yes, move pointer down 4k*/ - orl $0x0, (%ecx) /* probe there */ - subl $0x1000, %eax /* decrement count */ - cmpl $0x1000, %eax - ja Lprobe /* and do it again */ +/* ___chkstk is a *special* function call, which uses %rax as the argument. + We avoid clobbering the 4 integer argument registers, %rcx, %rdx, + %r8 and %r9, which leaves us with %rax, %r10, and %r11 to use. */ + .align 4 +___chkstk: + popq %r11 /* pop return address */ + cfi_adjust_cfa_offset(-8) /* indicate return address in r11 */ + cfi_register(%rip, %r11) + movq %rsp, %r10 + cmpq $0x1000, %rax /* > 4k ?*/ + jb 2f -Ldone: - subl %eax, %ecx - orl $0x0, (%ecx) /* less than 4k, just peek here */ +1: subq $0x1000, %r10 /* yes, move pointer down 4k*/ + orl $0x0, (%r10) /* probe there */ + subq $0x1000, %rax /* decrement count */ + cmpq $0x1000, %rax + ja 1b /* and do it again */ - movl %esp, %eax /* save old stack pointer */ - movl %ecx, %esp /* decrement stack */ - movl (%eax), %ecx /* recover saved temp */ - movl 4(%eax), %eax /* recover return address */ +2: subq %rax, %r10 + movq %rsp, %rax /* hold CFA until return */ + cfi_def_cfa_register(%rax) + orl $0x0, (%r10) /* less than 4k, just peek here */ + movq %r10, %rsp /* decrement stack */ /* Push the return value back. Doing this instead of just - jumping to %eax preserves the cached call-return stack + jumping to %r11 preserves the cached call-return stack used by most modern processors. */ - pushl %eax + pushq %r11 ret + cfi_endproc() #else -/* __alloca is a normal function call, which uses %rcx as the argument. And stack space - for the argument is saved. */ + cfi_startproc() +___chkstk: __alloca: - movq %rcx, %rax - addq $0x7, %rax - andq $0xfffffffffffffff8, %rax - popq %rcx /* pop return address */ - popq %r10 /* Pop the reserved stack space. */ - movq %rsp, %r10 /* get sp */ - cmpq $0x1000, %rax /* > 4k ?*/ - jb Ldone_alloca - -Lprobe_alloca: - subq $0x1000, %r10 /* yes, move pointer down 4k*/ - orq $0x0, (%r10) /* probe there */ - subq $0x1000, %rax /* decrement count */ - cmpq $0x1000, %rax - ja Lprobe_alloca /* and do it again */ + pushl %ecx /* save temp */ + cfi_push(%eax) + leal 8(%esp), %ecx /* point past return addr */ + cmpl $0x1000, %eax /* > 4k ?*/ + jb 2f + +1: subl $0x1000, %ecx /* yes, move pointer down 4k*/ + orl $0x0, (%ecx) /* probe there */ + subl $0x1000, %eax /* decrement count */ + cmpl $0x1000, %eax + ja 1b /* and do it again */ -Ldone_alloca: - subq %rax, %r10 - orq $0x0, (%r10) /* less than 4k, just peek here */ - movq %r10, %rax - subq $0x8, %r10 /* Reserve argument stack space. */ - movq %r10, %rsp /* decrement stack */ +2: subl %eax, %ecx + orl $0x0, (%ecx) /* less than 4k, just peek here */ + movl %esp, %eax /* save current stack pointer */ + cfi_def_cfa_register(%eax) + movl %ecx, %esp /* decrement stack */ + movl (%eax), %ecx /* recover saved temp */ - /* Push the return value back. Doing this instead of just - jumping to %rcx preserves the cached call-return stack - used by most modern processors. */ - pushq %rcx + /* Copy the return register. Doing this instead of just jumping to + the address preserves the cached call-return stack used by most + modern processors. */ + pushl 4(%eax) ret + cfi_endproc() +#endif /* _WIN64 */ +#endif /* L_chkstk */ -/* ___chkstk is a *special* function call, which uses %rax as the argument. - We avoid clobbering the 4 integer argument registers, %rcx, %rdx, - %r8 and %r9, which leaves us with %rax, %r10, and %r11 to use. */ -___chkstk: - addq $0x7, %rax /* Make sure stack is on alignment of 8. */ - andq $0xfffffffffffffff8, %rax - popq %r11 /* pop return address */ - movq %rsp, %r10 /* get sp */ - cmpq $0x1000, %rax /* > 4k ?*/ - jb Ldone - -Lprobe: - subq $0x1000, %r10 /* yes, move pointer down 4k*/ - orl $0x0, (%r10) /* probe there */ +#ifdef L_chkstk_ms +/* ___chkstk_ms is a *special* function call, which uses %rax as the argument. + We avoid clobbering any registers. Unlike ___chkstk, it just probes the + stack and does no stack allocation. */ + .global ___chkstk_ms +#ifdef _WIN64 + cfi_startproc() +___chkstk_ms: + pushq %rcx /* save temps */ + cfi_push(%rcx) + pushq %rax + cfi_push(%rax) + cmpq $0x1000, %rax /* > 4k ?*/ + leaq 24(%rsp), %rcx /* point past return addr */ + jb 2f + +1: subq $0x1000, %rcx /* yes, move pointer down 4k */ + orq $0x0, (%rcx) /* probe there */ subq $0x1000, %rax /* decrement count */ cmpq $0x1000, %rax - ja Lprobe /* and do it again */ + ja 1b /* and do it again */ -Ldone: - subq %rax, %r10 - orl $0x0, (%r10) /* less than 4k, just peek here */ - movq %r10, %rsp /* decrement stack */ +2: subq %rax, %rcx + orq $0x0, (%rcx) /* less than 4k, just peek here */ - /* Push the return value back. Doing this instead of just - jumping to %r11 preserves the cached call-return stack - used by most modern processors. */ - pushq %r11 + popq %rax + cfi_pop(%rax) + popq %rcx + cfi_pop(%rcx) + ret + cfi_endproc() +#else + cfi_startproc() +___chkstk_ms: + pushl %ecx /* save temp */ + cfi_push(%ecx) + pushl %eax + cfi_push(%eax) + cmpl $0x1000, %eax /* > 4k ?*/ + leal 12(%esp), %ecx /* point past return addr */ + jb 2f + +1: subl $0x1000, %ecx /* yes, move pointer down 4k*/ + orl $0x0, (%ecx) /* probe there */ + subl $0x1000, %eax /* decrement count */ + cmpl $0x1000, %eax + ja 1b /* and do it again */ + +2: subl %eax, %ecx + orl $0x0, (%ecx) /* less than 4k, just peek here */ + + popl %eax + cfi_pop(%eax) + popl %ecx + cfi_pop(%ecx) ret -#endif -#endif + cfi_endproc() +#endif /* _WIN64 */ +#endif /* L_chkstk_ms */ |