From 8163845fdab02ba1943b608b635873cee50df676 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Thu, 28 Jan 1999 22:09:12 +0000 Subject: Update. 1999-01-28 David S. Miller * sysdeps/sparc/sparc32/__longjmp.S: Rewrite without bogus sanity checks and aborts, to make longjmp based thread schemes work again. --- sysdeps/sparc/sparc32/__longjmp.S | 49 +++++++++++++++++++++++++-------------- 1 file changed, 32 insertions(+), 17 deletions(-) (limited to 'sysdeps/sparc') diff --git a/sysdeps/sparc/sparc32/__longjmp.S b/sysdeps/sparc/sparc32/__longjmp.S index cbd941fa82..6f984b98e9 100644 --- a/sysdeps/sparc/sparc32/__longjmp.S +++ b/sysdeps/sparc/sparc32/__longjmp.S @@ -1,4 +1,4 @@ -/* Copyright (C) 1991, 1993, 1996, 1997, 1998 Free Software Foundation, Inc. +/* Copyright (C) 1991, 93, 96, 97, 98, 99 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -19,20 +19,27 @@ #include #define _ASM 1 -#define _SETJMP_H -#include -#define ENV(reg) [%g1 + (reg * 4)] +#include +#define ENV(base,reg) [%base + (reg * 4)] +#define ST_FLUSH_WINDOWS 3 +#define RW_FP [%fp + 0x38] ENTRY(__longjmp) /* Store our arguments in global registers so we can still use them while unwinding frames and their register windows. */ + + ld ENV(o0,JB_FP), %g3 /* Cache target FP in register %g3. */ mov %o0, %g1 /* ENV in %g1 */ orcc %o1, %g0, %g2 /* VAL in %g2 */ be,a 0f /* Branch if zero; else skip delay slot. */ mov 1, %g2 /* Delay slot only hit if zero: VAL = 1. */ 0: - /* Cache target FP in register %g3. */ - ld ENV(JB_FP), %g3 + xor %fp, %g3, %o0 + add %fp, 512, %o1 + andncc %o0, 4095, %o0 + bne LOC(thread) + cmp %o1, %g3 + bl LOC(thread) /* Now we will loop, unwinding the register windows up the stack until the restored %fp value matches the target value in %g3. */ @@ -42,23 +49,31 @@ LOC(loop): bl,a LOC(loop) /* Loop while current fp is below target. */ restore /* Unwind register window in delay slot. */ be,a LOC(found) /* Better have hit it exactly. */ - ld ENV(JB_SP), %o0 /* Delay slot: extract target SP. */ + ld ENV(g1,JB_SP), %o0 /* Delay slot: extract target SP. */ -LOC(bogus): - /* Get here only if the jmp_buf or stack is clobbered. */ - call C_SYMBOL_NAME(abort) - nop - unimp 0 +LOC(thread): + /* + * Do a "flush register windows trap". The trap handler in the + * kernel writes all the register windows to their stack slots, and + * marks them all as invalid (needing to be sucked up from the + * stack when used). This ensures that all information needed to + * unwind to these callers is in memory, not in the register + * windows. + */ + ta ST_FLUSH_WINDOWS + ld ENV(g1,JB_PC), %o7 /* Set return PC. */ + ld ENV(g1,JB_SP), %fp /* Set saved SP on restore below. */ + sub %fp, 64, %sp /* Allocate a register frame. */ + st %g3, RW_FP /* Set saved FP on restore below. */ + retl + restore %g2, 0, %o0 /* Restore values from above register frame. */ LOC(found): /* We have unwound register windows so %fp matches the target. */ - cmp %o0, %sp /* Check jmp_buf SP vs register window. */ - bge,a LOC(sp_ok) /* Saved must not be deeper than register. */ - mov %o0, %sp /* OK, install new SP. */ - b,a LOC(bogus) /* Bogus, we lose. */ + mov %o0, %sp /* OK, install new SP. */ LOC(sp_ok): - ld ENV(JB_PC), %o0 /* Extract target return PC. */ + ld ENV(g1,JB_PC), %o0 /* Extract target return PC. */ jmp %o0 + 8 /* Return there. */ mov %g2, %o0 /* Delay slot: set return value. */ -- cgit 1.4.1