From 02fec4701cee79f875c1d02b8b4aee09380dbcb8 Mon Sep 17 00:00:00 2001 From: Guillaume Cottenceau Date: Thu, 4 Jan 2001 20:04:45 +0000 Subject: integrate dietlibc/stdio per default for cdrom and disk only installs --- mdk-stage1/dietlibc/sparc/__longjmp.S | 66 +++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 mdk-stage1/dietlibc/sparc/__longjmp.S (limited to 'mdk-stage1/dietlibc/sparc/__longjmp.S') diff --git a/mdk-stage1/dietlibc/sparc/__longjmp.S b/mdk-stage1/dietlibc/sparc/__longjmp.S new file mode 100644 index 000000000..81dd24af2 --- /dev/null +++ b/mdk-stage1/dietlibc/sparc/__longjmp.S @@ -0,0 +1,66 @@ +#define _ASM +#define _SETJMP_H +#include + + +#define ENV(base,reg) [%base + (reg * 4)] +#define ST_FLUSH_WINDOWS 3 +#define RW_FP [%fp + 0x48] + +.text +.global __longjmp +__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: + xor %fp, %g3, %o0 + add %fp, 512, %o1 + andncc %o0, 4095, %o0 + bne .Lthread + cmp %o1, %g3 + bl .Lthread + + /* Now we will loop, unwinding the register windows up the stack + until the restored %fp value matches the target value in %g3. */ + +.Lloop: + cmp %fp, %g3 /* Have we reached the target frame? */ + bl,a .Lloop /* Loop while current fp is below target. */ + restore /* Unwind register window in delay slot. */ + be,a .Lfound /* Better have hit it exactly. */ + ld ENV(g1,JB_SP), %o0 /* Delay slot: extract target SP. */ + +.Lthread: + /* + * 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. */ + +.Lfound: + /* We have unwound register windows so %fp matches the target. */ + mov %o0, %sp /* OK, install new SP. */ + +.Lsp_ok: + ld ENV(g1,JB_PC), %o0 /* Extract target return PC. */ + jmp %o0 + 8 /* Return there. */ + mov %g2, %o0 /* Delay slot: set return value. */ + +.size __longjmp, . - __longjmp + -- cgit v1.2.1