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Diffstat (limited to 'sysdeps/alpha/div_libc.h')
| -rw-r--r-- | sysdeps/alpha/div_libc.h | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/sysdeps/alpha/div_libc.h b/sysdeps/alpha/div_libc.h new file mode 100644 index 0000000000..98566435ce --- /dev/null +++ b/sysdeps/alpha/div_libc.h @@ -0,0 +1,113 @@ +/* Copyright (C) 2004 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +/* Common bits for implementing software divide. */ + +#include <sysdep.h> +#ifdef __linux__ +# include <asm/gentrap.h> +# include <asm/pal.h> +#else +# include <machine/pal.h> +#endif + +/* These are not normal C functions. Argument registers are t10 and t11; + the result goes in t12; the return address is in t9. Only t12 and AT + may be clobbered. */ +#define X t10 +#define Y t11 +#define RV t12 +#define RA t9 + +/* None of these functions should use implicit anything. */ + .set nomacro + .set noat + +/* Code fragment to invoke _mcount for profiling. This should be invoked + directly after allocation of the stack frame. */ +.macro CALL_MCOUNT +#ifdef PROF + stq ra, 0(sp) + stq pv, 8(sp) + stq gp, 16(sp) + cfi_rel_offset (ra, 0) + cfi_rel_offset (pv, 8) + cfi_rel_offset (gp, 16) + br AT, 1f + .set macro +1: ldgp gp, 0(AT) + mov RA, ra + lda AT, _mcount + jsr AT, (AT), _mcount + .set nomacro + ldq ra, 0(sp) + ldq pv, 8(sp) + ldq gp, 16(sp) + cfi_restore (ra) + cfi_restore (pv) + cfi_restore (gp) + /* Realign subsequent code with what we'd have without this + macro at all. This means aligned with one arithmetic insn + used within the bundle. */ + .align 4 + nop +#endif +.endm + +/* In order to make the below work, all top-level divide routines must + use the same frame size. */ +#define FRAME 48 + +/* Code fragment to generate an integer divide-by-zero fault. When + building libc.so, we arrange for there to be one copy of this code + placed late in the dso, such that all branches are forward. When + building libc.a, we use multiple copies to avoid having an out of + range branch. Users should jump to DIVBYZERO. */ + +.macro DO_DIVBYZERO +#ifdef PIC +#define DIVBYZERO __divbyzero + .section .gnu.linkonce.t.divbyzero, "ax", @progbits + .globl __divbyzero + .type __divbyzero, @function + .usepv __divbyzero, no + .hidden __divbyzero +#else +#define DIVBYZERO $divbyzero +#endif + + .align 4 +DIVBYZERO: + cfi_startproc + cfi_return_column (RA) + cfi_def_cfa_offset (FRAME) + + mov a0, RV + unop + lda a0, GEN_INTDIV + call_pal PAL_gentrap + + mov RV, a0 + clr RV + lda sp, FRAME(sp) + cfi_def_cfa_offset (0) + ret $31, (RA), 1 + + cfi_endproc + .size DIVBYZERO, .-DIVBYZERO +.endm |