/* decode_i586: asm synth copyright ?-2006 by the mpg123 project - free software under the terms of the LGPL 2.1 see COPYING and AUTHORS files in distribution or http://mpg123.org initially written by Stefan Bieschewski synth_1to1 works the same way as the c version of this file. only two types of changes have been made: - reordered floating point instructions to prevent pipline stalls - made WRITE_SAMPLE use integer instead of (slower) floating point all kinds of x86 processors should benefit from these modifications. useful sources of information on optimizing x86 code include: Intel Architecture Optimization Manual http://www.intel.com/design/pentium/manuals/242816.htm Cyrix 6x86 Instruction Set Summary ftp://ftp.cyrix.com/6x86/6x-dbch6.pdf AMD-K5 Processor Software Development http://www.amd.com/products/cpg/techdocs/appnotes/20007e.pdf Stefan Bieschewski $Id: decode_i586.s 1 2004-09-18 13:30:08Z thomas $ */ #include "mangle.h" .data #ifndef __APPLE__ .section .rodata #endif ALIGN8 .LC0: .long 0x0,0x40dfffc0 ALIGN8 .LC1: .long 0x0,0xc0e00000 ALIGN8 .text /* int synth_1to1_i586_asm(real *bandPtr, int channel, unsigned char *out, unsigned char *buffs, int *bo, real *decwin); */ .globl ASM_NAME(synth_1to1_i586_asm) ASM_NAME(synth_1to1_i586_asm): subl $12,%esp pushl %ebp pushl %edi pushl %esi pushl %ebx /* stack: 0=ebx, 4=esi, 8=edi, 12=ebp, 16,20,24=local, 28=back, 32=bandPtr, 36=channel, 40=out, 44=buffs, 48=bo, 52=decwin */ movl 32(%esp),%eax /* *bandPtr */ movl 40(%esp),%esi /* *out */ movl 48(%esp),%edi /* *bo */ movl (%edi),%ebp /* store bo value in ebp */ xorl %edi,%edi cmpl %edi,36(%esp) jne .L48 /* if(!channel) */ decl %ebp /* bo-- */ andl $15,%ebp /* bo &= 0xf */ movl 48(%esp), %edi /* *bo */ movl %ebp,(%edi) /* write back bo */ xorl %edi,%edi /* restore %edi to 0; it's used later */ movl 44(%esp),%ecx /* use buffs */ jmp .L49 .L48: /* if(channel) use buffs+2176 */ addl $2,%esi movl 44(%esp),%ecx /* *buffs */ addl $2176,%ecx .L49: testl $1,%ebp je .L50 movl %ecx,%ebx movl %ebp,16(%esp) pushl %eax movl 20(%esp),%edx leal (%ebx,%edx,4),%eax pushl %eax movl 24(%esp),%eax incl %eax andl $15,%eax leal 1088(,%eax,4),%eax addl %ebx,%eax jmp .L74 .L50: leal 1088(%ecx),%ebx leal 1(%ebp),%edx movl %edx,16(%esp) pushl %eax leal 1092(%ecx,%ebp,4),%eax pushl %eax leal (%ecx,%ebp,4),%eax .L74: pushl %eax call FUNC(dct64_i386) addl $12,%esp /* stack now back on track */ movl 16(%esp),%edx leal 0(,%edx,4),%edx movl 52(%esp),%eax /* decwin */ addl $64,%eax movl %eax,%ecx subl %edx,%ecx movl $16,%ebp .L55: flds (%ecx) fmuls (%ebx) flds 4(%ecx) fmuls 4(%ebx) fxch %st(1) flds 8(%ecx) fmuls 8(%ebx) fxch %st(2) fsubrp %st,%st(1) flds 12(%ecx) fmuls 12(%ebx) fxch %st(2) faddp %st,%st(1) flds 16(%ecx) fmuls 16(%ebx) fxch %st(2) fsubrp %st,%st(1) flds 20(%ecx) fmuls 20(%ebx) fxch %st(2) faddp %st,%st(1) flds 24(%ecx) fmuls 24(%ebx) fxch %st(2) fsubrp %st,%st(1) flds 28(%ecx) fmuls 28(%ebx) fxch %st(2) faddp %st,%st(1) flds 32(%ecx) fmuls 32(%ebx) fxch %st(2) fsubrp %st,%st(1) flds 36(%ecx) fmuls 36(%ebx) fxch %st(2) faddp %st,%st(1) flds 40(%ecx) fmuls 40(%ebx) fxch %st(2) fsubrp %st,%st(1) flds 44(%ecx) fmuls 44(%ebx) fxch %st(2) faddp %st,%st(1) flds 48(%ecx) fmuls 48(%ebx) fxch %st(2) fsubrp %st,%st(1) flds 52(%ecx) fmuls 52(%ebx) fxch %st(2) faddp %st,%st(1) flds 56(%ecx) fmuls 56(%ebx) fxch %st(2) fsubrp %st,%st(1) flds 60(%ecx) fmuls 60(%ebx) fxch %st(2) subl $4,%esp faddp %st,%st(1) fxch %st(1) fsubrp %st,%st(1) fistpl (%esp) popl %eax cmpl $32767,%eax jg 1f cmpl $-32768,%eax jl 2f movw %ax,(%esi) jmp 4f 1: movw $32767,(%esi) jmp 3f 2: movw $-32768,(%esi) 3: incl %edi 4: .L54: addl $64,%ebx subl $-128,%ecx addl $4,%esi decl %ebp jnz .L55 flds (%ecx) fmuls (%ebx) flds 8(%ecx) fmuls 8(%ebx) flds 16(%ecx) fmuls 16(%ebx) fxch %st(2) faddp %st,%st(1) flds 24(%ecx) fmuls 24(%ebx) fxch %st(2) faddp %st,%st(1) flds 32(%ecx) fmuls 32(%ebx) fxch %st(2) faddp %st,%st(1) flds 40(%ecx) fmuls 40(%ebx) fxch %st(2) faddp %st,%st(1) flds 48(%ecx) fmuls 48(%ebx) fxch %st(2) faddp %st,%st(1) flds 56(%ecx) fmuls 56(%ebx) fxch %st(2) subl $4,%esp faddp %st,%st(1) fxch %st(1) faddp %st,%st(1) fistpl (%esp) popl %eax cmpl $32767,%eax jg 1f cmpl $-32768,%eax jl 2f movw %ax,(%esi) jmp 4f 1: movw $32767,(%esi) jmp 3f 2: movw $-32768,(%esi) 3: incl %edi 4: .L62: addl $-64,%ebx addl $4,%esi movl 16(%esp),%edx leal -128(%ecx,%edx,8),%ecx movl $15,%ebp .L68: flds -4(%ecx) fchs fmuls (%ebx) flds -8(%ecx) fmuls 4(%ebx) fxch %st(1) flds -12(%ecx) fmuls 8(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -16(%ecx) fmuls 12(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -20(%ecx) fmuls 16(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -24(%ecx) fmuls 20(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -28(%ecx) fmuls 24(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -32(%ecx) fmuls 28(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -36(%ecx) fmuls 32(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -40(%ecx) fmuls 36(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -44(%ecx) fmuls 40(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -48(%ecx) fmuls 44(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -52(%ecx) fmuls 48(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -56(%ecx) fmuls 52(%ebx) fxch %st(2) fsubrp %st,%st(1) flds -60(%ecx) fmuls 56(%ebx) fxch %st(2) fsubrp %st,%st(1) flds (%ecx) fmuls 60(%ebx) fxch %st(2) subl $4,%esp fsubrp %st,%st(1) fxch %st(1) fsubrp %st,%st(1) fistpl (%esp) popl %eax cmpl $32767,%eax jg 1f cmpl $-32768,%eax jl 2f movw %ax,(%esi) jmp 4f 1: movw $32767,(%esi) jmp 3f 2: movw $-32768,(%esi) 3: incl %edi 4: .L67: addl $-64,%ebx addl $-128,%ecx addl $4,%esi decl %ebp jnz .L68 movl %edi,%eax popl %ebx popl %esi popl %edi popl %ebp addl $12,%esp ret #if defined(PIC) && defined(__APPLE__) .section __IMPORT,__jump_table,symbol_stubs,self_modifying_code+pure_instructions,5 L_dct64_i386: .indirect_symbol ASM_NAME(dct64_i386) hlt ; hlt ; hlt ; hlt ; hlt #endif NONEXEC_STACK