diff options
Diffstat (limited to 'newlib/libc/machine/spu/stack_reg_va.S')
| -rw-r--r-- | newlib/libc/machine/spu/stack_reg_va.S | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/newlib/libc/machine/spu/stack_reg_va.S b/newlib/libc/machine/spu/stack_reg_va.S new file mode 100644 index 000000000..5a0b632e8 --- /dev/null +++ b/newlib/libc/machine/spu/stack_reg_va.S @@ -0,0 +1,166 @@ +/* + Copyright (c) 2007, Toshiba Corporation + + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + * Neither the names of Toshiba nor the names of its + contributors may be used to endorse or promote products derived from this + software without specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + POSSIBILITY OF SUCH DAMAGE. + */ +/* + * This file contains code use to construct a PIC, spu side, syscall + * function with variable parameters in accordance with the CBE ABI. + * + * This function is equivalent to constructing a va_list structure and + * calling the va_list form of the function. Therefore, for example, + * a printf function stack frame will look like this: + * + * | Stack | high memory + * | Parms | + * | | + * |------------| + * | Link Reg | + * |------------| + * | Back Chain |<-----. <---- input SP + * |------------| | + * | Reg 74 | | + * |------------| | + * | Reg 73 | | + * |------------| | + * // ... // | + * |------------| | + * | Reg 5 | | + * |------------| | + * | Reg 4 |<--. | + * |------------| | | + * va_list.| call_stack |------' + * |------------| | + * va_list.| next_arg |---' + * |------------| + * | format (r3)| <---- start of parameters + * |------------| |------------| + * | stack | | | + * | code | |(Back Chain)| <---- output SP + * | 1-3 qwords | <---- code_ptr `------------' + * `------------' + * low memory + * + * This was written in assembly so that it is smaller than what would + * be produced by using va_start. + */ + +#include "c99ppe.h" + +#define parms $2 /* Number of fixed arguments */ + +#define offset $67 +#define flag $68 +#define regdec $69 +#define link $70 + +#define code_ptr $71 +#define ptr $72 +#define inst $73 +#define tmp $74 + + .text + .global __stack_reg_va + +__stack_reg_va: + + /* Save registers 69-74 explicitly so that we have some + * working registers. + */ + stqd $74, 16*(-1)($sp) + stqd $73, 16*(-2)($sp) + stqd $72, 16*(-3)($sp) + stqd $71, 16*(-4)($sp) + stqd $70, 16*(-5)($sp) + stqd $69, 16*(-6)($sp) + + /* Construct self-modifying stack code that saves the remaining + * volatile registers onto the stack. + */ + il regdec, -1 /* for decrement register value in save instruction */ + shlqbyi regdec, regdec, 12 + il tmp, -(SPE_STACK_REGS+2+3)*16 + a code_ptr, $sp, tmp + lqr tmp, save_regs_1 /* store stack code */ + stqd tmp, 0(code_ptr) + lqr inst, save_regs_2 + ai ptr, $sp, 16*(-6) + sync + bisl link, code_ptr /* branch to the constructed stack code */ + + /* Adjust pointer so that it points to the first variable + * argument on the stack. + */ + ai offset, parms, -1 /* offset = parms - 1 */ + mpyi offset, offset, 16 /* offset = offset * 16 */ + a ptr, ptr, offset /* ptr = ptr + offset */ + + /* Store the va_list to the parameter list. + */ + stqd $sp, 16*(-1)(ptr) + stqd ptr, 16*(-2)(ptr) + + /* Make $3 store address. + */ + ai offset, parms, 2 /* offset = parms + 2 */ + mpyi offset, offset, -16 /* offset = offset * -16 */ + a ptr, ptr, offset /* ptr = ptr + offset */ + + /* Save all the fixed (non-variable arguments on the stack) + */ + ceqi flag, parms, 0x01 /* if(parms==1) flag=0xFFFFFFFF */ + brnz flag, reg_3 /* if(flag!=0) jump */ + ceqi flag, parms, 0x02 /* if(parms==2) flag=0xFFFFFFFF */ + brnz flag, reg_4 /* if(flag!=0) jump */ + stqd $5, 16*2(ptr) +reg_4: + stqd $4, 16*1(ptr) +reg_3: + stqd $3, 0(ptr) + + il $3, -16*(SPE_STACK_REGS+2+2) + stqx $sp, $3, $sp /* save back chain */ + a $sp, $sp, $3 + bi $0 /* return to caller */ + +/***************************** stack code *********************************************/ + + /* The following code is copied into the stack for re-entract, + * self-modified, code execution. This code copies the volatile + * registers into a va_list parameter array. + */ + .balignl 16, 0 +save_regs_1: + stqd inst, 16(code_ptr) /* store instruction */ + sync + a inst, inst, regdec /* decrement register number in the instruction */ + ceqbi tmp, inst, 3 /* if (reg-num == 3) tmp = 0x000000FF 000..0 */ +save_regs_2: + stqd $68, -16(ptr) + ai ptr, ptr, -16 + brz tmp, save_regs_1 /* if (tmp == 0) jump */ + bi link /* finish to make va_list */ |