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Diffstat (limited to 'media/libjpeg/simd/i386/jchuff-sse2.asm')
| -rw-r--r-- | media/libjpeg/simd/i386/jchuff-sse2.asm | 423 |
1 files changed, 423 insertions, 0 deletions
diff --git a/media/libjpeg/simd/i386/jchuff-sse2.asm b/media/libjpeg/simd/i386/jchuff-sse2.asm new file mode 100644 index 0000000000..d0112e6107 --- /dev/null +++ b/media/libjpeg/simd/i386/jchuff-sse2.asm @@ -0,0 +1,423 @@ +; +; jchuff-sse2.asm - Huffman entropy encoding (SSE2) +; +; Copyright (C) 2009-2011, 2014-2017, D. R. Commander. +; Copyright (C) 2015, Matthieu Darbois. +; +; Based on the x86 SIMD extension for IJG JPEG library +; Copyright (C) 1999-2006, MIYASAKA Masaru. +; For conditions of distribution and use, see copyright notice in jsimdext.inc +; +; This file should be assembled with NASM (Netwide Assembler), +; can *not* be assembled with Microsoft's MASM or any compatible +; assembler (including Borland's Turbo Assembler). +; NASM is available from http://nasm.sourceforge.net/ or +; http://sourceforge.net/project/showfiles.php?group_id=6208 +; +; This file contains an SSE2 implementation for Huffman coding of one block. +; The following code is based directly on jchuff.c; see jchuff.c for more +; details. + +%include "jsimdext.inc" + +; -------------------------------------------------------------------------- + SECTION SEG_CONST + + alignz 32 + GLOBAL_DATA(jconst_huff_encode_one_block) + EXTERN EXTN(jpeg_nbits_table) + +EXTN(jconst_huff_encode_one_block): + + alignz 32 + +; -------------------------------------------------------------------------- + SECTION SEG_TEXT + BITS 32 + +; These macros perform the same task as the emit_bits() function in the +; original libjpeg code. In addition to reducing overhead by explicitly +; inlining the code, additional performance is achieved by taking into +; account the size of the bit buffer and waiting until it is almost full +; before emptying it. This mostly benefits 64-bit platforms, since 6 +; bytes can be stored in a 64-bit bit buffer before it has to be emptied. + +%macro EMIT_BYTE 0 + sub put_bits, 8 ; put_bits -= 8; + mov edx, put_buffer + mov ecx, put_bits + shr edx, cl ; c = (JOCTET)GETJOCTET(put_buffer >> put_bits); + mov byte [eax], dl ; *buffer++ = c; + add eax, 1 + cmp dl, 0xFF ; need to stuff a zero byte? + jne %%.EMIT_BYTE_END + mov byte [eax], 0 ; *buffer++ = 0; + add eax, 1 +%%.EMIT_BYTE_END: +%endmacro + +%macro PUT_BITS 1 + add put_bits, ecx ; put_bits += size; + shl put_buffer, cl ; put_buffer = (put_buffer << size); + or put_buffer, %1 +%endmacro + +%macro CHECKBUF15 0 + cmp put_bits, 16 ; if (put_bits > 31) { + jl %%.CHECKBUF15_END + mov eax, POINTER [esp+buffer] + EMIT_BYTE + EMIT_BYTE + mov POINTER [esp+buffer], eax +%%.CHECKBUF15_END: +%endmacro + +%macro EMIT_BITS 1 + PUT_BITS %1 + CHECKBUF15 +%endmacro + +%macro kloop_prepare 37 ;(ko, jno0, ..., jno31, xmm0, xmm1, xmm2, xmm3) + pxor xmm4, xmm4 ; __m128i neg = _mm_setzero_si128(); + pxor xmm5, xmm5 ; __m128i neg = _mm_setzero_si128(); + pxor xmm6, xmm6 ; __m128i neg = _mm_setzero_si128(); + pxor xmm7, xmm7 ; __m128i neg = _mm_setzero_si128(); + pinsrw %34, word [esi + %2 * SIZEOF_WORD], 0 ; xmm_shadow[0] = block[jno0]; + pinsrw %35, word [esi + %10 * SIZEOF_WORD], 0 ; xmm_shadow[8] = block[jno8]; + pinsrw %36, word [esi + %18 * SIZEOF_WORD], 0 ; xmm_shadow[16] = block[jno16]; + pinsrw %37, word [esi + %26 * SIZEOF_WORD], 0 ; xmm_shadow[24] = block[jno24]; + pinsrw %34, word [esi + %3 * SIZEOF_WORD], 1 ; xmm_shadow[1] = block[jno1]; + pinsrw %35, word [esi + %11 * SIZEOF_WORD], 1 ; xmm_shadow[9] = block[jno9]; + pinsrw %36, word [esi + %19 * SIZEOF_WORD], 1 ; xmm_shadow[17] = block[jno17]; + pinsrw %37, word [esi + %27 * SIZEOF_WORD], 1 ; xmm_shadow[25] = block[jno25]; + pinsrw %34, word [esi + %4 * SIZEOF_WORD], 2 ; xmm_shadow[2] = block[jno2]; + pinsrw %35, word [esi + %12 * SIZEOF_WORD], 2 ; xmm_shadow[10] = block[jno10]; + pinsrw %36, word [esi + %20 * SIZEOF_WORD], 2 ; xmm_shadow[18] = block[jno18]; + pinsrw %37, word [esi + %28 * SIZEOF_WORD], 2 ; xmm_shadow[26] = block[jno26]; + pinsrw %34, word [esi + %5 * SIZEOF_WORD], 3 ; xmm_shadow[3] = block[jno3]; + pinsrw %35, word [esi + %13 * SIZEOF_WORD], 3 ; xmm_shadow[11] = block[jno11]; + pinsrw %36, word [esi + %21 * SIZEOF_WORD], 3 ; xmm_shadow[19] = block[jno19]; + pinsrw %37, word [esi + %29 * SIZEOF_WORD], 3 ; xmm_shadow[27] = block[jno27]; + pinsrw %34, word [esi + %6 * SIZEOF_WORD], 4 ; xmm_shadow[4] = block[jno4]; + pinsrw %35, word [esi + %14 * SIZEOF_WORD], 4 ; xmm_shadow[12] = block[jno12]; + pinsrw %36, word [esi + %22 * SIZEOF_WORD], 4 ; xmm_shadow[20] = block[jno20]; + pinsrw %37, word [esi + %30 * SIZEOF_WORD], 4 ; xmm_shadow[28] = block[jno28]; + pinsrw %34, word [esi + %7 * SIZEOF_WORD], 5 ; xmm_shadow[5] = block[jno5]; + pinsrw %35, word [esi + %15 * SIZEOF_WORD], 5 ; xmm_shadow[13] = block[jno13]; + pinsrw %36, word [esi + %23 * SIZEOF_WORD], 5 ; xmm_shadow[21] = block[jno21]; + pinsrw %37, word [esi + %31 * SIZEOF_WORD], 5 ; xmm_shadow[29] = block[jno29]; + pinsrw %34, word [esi + %8 * SIZEOF_WORD], 6 ; xmm_shadow[6] = block[jno6]; + pinsrw %35, word [esi + %16 * SIZEOF_WORD], 6 ; xmm_shadow[14] = block[jno14]; + pinsrw %36, word [esi + %24 * SIZEOF_WORD], 6 ; xmm_shadow[22] = block[jno22]; + pinsrw %37, word [esi + %32 * SIZEOF_WORD], 6 ; xmm_shadow[30] = block[jno30]; + pinsrw %34, word [esi + %9 * SIZEOF_WORD], 7 ; xmm_shadow[7] = block[jno7]; + pinsrw %35, word [esi + %17 * SIZEOF_WORD], 7 ; xmm_shadow[15] = block[jno15]; + pinsrw %36, word [esi + %25 * SIZEOF_WORD], 7 ; xmm_shadow[23] = block[jno23]; +%if %1 != 32 + pinsrw %37, word [esi + %33 * SIZEOF_WORD], 7 ; xmm_shadow[31] = block[jno31]; +%else + pinsrw %37, ecx, 7 ; xmm_shadow[31] = block[jno31]; +%endif + pcmpgtw xmm4, %34 ; neg = _mm_cmpgt_epi16(neg, x1); + pcmpgtw xmm5, %35 ; neg = _mm_cmpgt_epi16(neg, x1); + pcmpgtw xmm6, %36 ; neg = _mm_cmpgt_epi16(neg, x1); + pcmpgtw xmm7, %37 ; neg = _mm_cmpgt_epi16(neg, x1); + paddw %34, xmm4 ; x1 = _mm_add_epi16(x1, neg); + paddw %35, xmm5 ; x1 = _mm_add_epi16(x1, neg); + paddw %36, xmm6 ; x1 = _mm_add_epi16(x1, neg); + paddw %37, xmm7 ; x1 = _mm_add_epi16(x1, neg); + pxor %34, xmm4 ; x1 = _mm_xor_si128(x1, neg); + pxor %35, xmm5 ; x1 = _mm_xor_si128(x1, neg); + pxor %36, xmm6 ; x1 = _mm_xor_si128(x1, neg); + pxor %37, xmm7 ; x1 = _mm_xor_si128(x1, neg); + pxor xmm4, %34 ; neg = _mm_xor_si128(neg, x1); + pxor xmm5, %35 ; neg = _mm_xor_si128(neg, x1); + pxor xmm6, %36 ; neg = _mm_xor_si128(neg, x1); + pxor xmm7, %37 ; neg = _mm_xor_si128(neg, x1); + movdqa XMMWORD [esp + t1 + %1 * SIZEOF_WORD], %34 ; _mm_storeu_si128((__m128i *)(t1 + ko), x1); + movdqa XMMWORD [esp + t1 + (%1 + 8) * SIZEOF_WORD], %35 ; _mm_storeu_si128((__m128i *)(t1 + ko + 8), x1); + movdqa XMMWORD [esp + t1 + (%1 + 16) * SIZEOF_WORD], %36 ; _mm_storeu_si128((__m128i *)(t1 + ko + 16), x1); + movdqa XMMWORD [esp + t1 + (%1 + 24) * SIZEOF_WORD], %37 ; _mm_storeu_si128((__m128i *)(t1 + ko + 24), x1); + movdqa XMMWORD [esp + t2 + %1 * SIZEOF_WORD], xmm4 ; _mm_storeu_si128((__m128i *)(t2 + ko), neg); + movdqa XMMWORD [esp + t2 + (%1 + 8) * SIZEOF_WORD], xmm5 ; _mm_storeu_si128((__m128i *)(t2 + ko + 8), neg); + movdqa XMMWORD [esp + t2 + (%1 + 16) * SIZEOF_WORD], xmm6 ; _mm_storeu_si128((__m128i *)(t2 + ko + 16), neg); + movdqa XMMWORD [esp + t2 + (%1 + 24) * SIZEOF_WORD], xmm7 ; _mm_storeu_si128((__m128i *)(t2 + ko + 24), neg); +%endmacro + +; +; Encode a single block's worth of coefficients. +; +; GLOBAL(JOCTET *) +; jsimd_huff_encode_one_block_sse2(working_state *state, JOCTET *buffer, +; JCOEFPTR block, int last_dc_val, +; c_derived_tbl *dctbl, c_derived_tbl *actbl) +; + +; eax + 8 = working_state *state +; eax + 12 = JOCTET *buffer +; eax + 16 = JCOEFPTR block +; eax + 20 = int last_dc_val +; eax + 24 = c_derived_tbl *dctbl +; eax + 28 = c_derived_tbl *actbl + +%define pad 6 * SIZEOF_DWORD ; Align to 16 bytes +%define t1 pad +%define t2 t1 + (DCTSIZE2 * SIZEOF_WORD) +%define block t2 + (DCTSIZE2 * SIZEOF_WORD) +%define actbl block + SIZEOF_DWORD +%define buffer actbl + SIZEOF_DWORD +%define temp buffer + SIZEOF_DWORD +%define temp2 temp + SIZEOF_DWORD +%define temp3 temp2 + SIZEOF_DWORD +%define temp4 temp3 + SIZEOF_DWORD +%define temp5 temp4 + SIZEOF_DWORD +%define gotptr temp5 + SIZEOF_DWORD ; void *gotptr +%define put_buffer ebx +%define put_bits edi + + align 32 + GLOBAL_FUNCTION(jsimd_huff_encode_one_block_sse2) + +EXTN(jsimd_huff_encode_one_block_sse2): + push ebp + mov eax, esp ; eax = original ebp + sub esp, byte 4 + and esp, byte (-SIZEOF_XMMWORD) ; align to 128 bits + mov [esp], eax + mov ebp, esp ; ebp = aligned ebp + sub esp, temp5+9*SIZEOF_DWORD-pad + push ebx + push ecx +; push edx ; need not be preserved + push esi + push edi + push ebp + + mov esi, POINTER [eax+8] ; (working_state *state) + mov put_buffer, dword [esi+8] ; put_buffer = state->cur.put_buffer; + mov put_bits, dword [esi+12] ; put_bits = state->cur.put_bits; + push esi ; esi is now scratch + + get_GOT edx ; get GOT address + movpic POINTER [esp+gotptr], edx ; save GOT address + + mov ecx, POINTER [eax+28] + mov edx, POINTER [eax+16] + mov esi, POINTER [eax+12] + mov POINTER [esp+actbl], ecx + mov POINTER [esp+block], edx + mov POINTER [esp+buffer], esi + + ; Encode the DC coefficient difference per section F.1.2.1 + mov esi, POINTER [esp+block] ; block + movsx ecx, word [esi] ; temp = temp2 = block[0] - last_dc_val; + sub ecx, dword [eax+20] + mov esi, ecx + + ; This is a well-known technique for obtaining the absolute value + ; with out a branch. It is derived from an assembly language technique + ; presented in "How to Optimize for the Pentium Processors", + ; Copyright (c) 1996, 1997 by Agner Fog. + mov edx, ecx + sar edx, 31 ; temp3 = temp >> (CHAR_BIT * sizeof(int) - 1); + xor ecx, edx ; temp ^= temp3; + sub ecx, edx ; temp -= temp3; + + ; For a negative input, want temp2 = bitwise complement of abs(input) + ; This code assumes we are on a two's complement machine + add esi, edx ; temp2 += temp3; + mov dword [esp+temp], esi ; backup temp2 in temp + + ; Find the number of bits needed for the magnitude of the coefficient + movpic ebp, POINTER [esp+gotptr] ; load GOT address (ebp) + movzx edx, byte [GOTOFF(ebp, EXTN(jpeg_nbits_table) + ecx)] ; nbits = JPEG_NBITS(temp); + mov dword [esp+temp2], edx ; backup nbits in temp2 + + ; Emit the Huffman-coded symbol for the number of bits + mov ebp, POINTER [eax+24] ; After this point, arguments are not accessible anymore + mov eax, INT [ebp + edx * 4] ; code = dctbl->ehufco[nbits]; + movzx ecx, byte [ebp + edx + 1024] ; size = dctbl->ehufsi[nbits]; + EMIT_BITS eax ; EMIT_BITS(code, size) + + mov ecx, dword [esp+temp2] ; restore nbits + + ; Mask off any extra bits in code + mov eax, 1 + shl eax, cl + dec eax + and eax, dword [esp+temp] ; temp2 &= (((JLONG)1)<<nbits) - 1; + + ; Emit that number of bits of the value, if positive, + ; or the complement of its magnitude, if negative. + EMIT_BITS eax ; EMIT_BITS(temp2, nbits) + + ; Prepare data + xor ecx, ecx + mov esi, POINTER [esp+block] + kloop_prepare 0, 1, 8, 16, 9, 2, 3, 10, 17, 24, 32, 25, \ + 18, 11, 4, 5, 12, 19, 26, 33, 40, 48, 41, 34, \ + 27, 20, 13, 6, 7, 14, 21, 28, 35, \ + xmm0, xmm1, xmm2, xmm3 + kloop_prepare 32, 42, 49, 56, 57, 50, 43, 36, 29, 22, 15, 23, \ + 30, 37, 44, 51, 58, 59, 52, 45, 38, 31, 39, 46, \ + 53, 60, 61, 54, 47, 55, 62, 63, 63, \ + xmm0, xmm1, xmm2, xmm3 + + pxor xmm7, xmm7 + movdqa xmm0, XMMWORD [esp + t1 + 0 * SIZEOF_WORD] ; __m128i tmp0 = _mm_loadu_si128((__m128i *)(t1 + 0)); + movdqa xmm1, XMMWORD [esp + t1 + 8 * SIZEOF_WORD] ; __m128i tmp1 = _mm_loadu_si128((__m128i *)(t1 + 8)); + movdqa xmm2, XMMWORD [esp + t1 + 16 * SIZEOF_WORD] ; __m128i tmp2 = _mm_loadu_si128((__m128i *)(t1 + 16)); + movdqa xmm3, XMMWORD [esp + t1 + 24 * SIZEOF_WORD] ; __m128i tmp3 = _mm_loadu_si128((__m128i *)(t1 + 24)); + pcmpeqw xmm0, xmm7 ; tmp0 = _mm_cmpeq_epi16(tmp0, zero); + pcmpeqw xmm1, xmm7 ; tmp1 = _mm_cmpeq_epi16(tmp1, zero); + pcmpeqw xmm2, xmm7 ; tmp2 = _mm_cmpeq_epi16(tmp2, zero); + pcmpeqw xmm3, xmm7 ; tmp3 = _mm_cmpeq_epi16(tmp3, zero); + packsswb xmm0, xmm1 ; tmp0 = _mm_packs_epi16(tmp0, tmp1); + packsswb xmm2, xmm3 ; tmp2 = _mm_packs_epi16(tmp2, tmp3); + pmovmskb edx, xmm0 ; index = ((uint64_t)_mm_movemask_epi8(tmp0)) << 0; + pmovmskb ecx, xmm2 ; index = ((uint64_t)_mm_movemask_epi8(tmp2)) << 16; + shl ecx, 16 + or edx, ecx + not edx ; index = ~index; + + lea esi, [esp+t1] + mov ebp, POINTER [esp+actbl] ; ebp = actbl + +.BLOOP: + bsf ecx, edx ; r = __builtin_ctzl(index); + jz near .ELOOP + lea esi, [esi+ecx*2] ; k += r; + shr edx, cl ; index >>= r; + mov dword [esp+temp3], edx +.BRLOOP: + cmp ecx, 16 ; while (r > 15) { + jl near .ERLOOP + sub ecx, 16 ; r -= 16; + mov dword [esp+temp], ecx + mov eax, INT [ebp + 240 * 4] ; code_0xf0 = actbl->ehufco[0xf0]; + movzx ecx, byte [ebp + 1024 + 240] ; size_0xf0 = actbl->ehufsi[0xf0]; + EMIT_BITS eax ; EMIT_BITS(code_0xf0, size_0xf0) + mov ecx, dword [esp+temp] + jmp .BRLOOP +.ERLOOP: + movsx eax, word [esi] ; temp = t1[k]; + movpic edx, POINTER [esp+gotptr] ; load GOT address (edx) + movzx eax, byte [GOTOFF(edx, EXTN(jpeg_nbits_table) + eax)] ; nbits = JPEG_NBITS(temp); + mov dword [esp+temp2], eax + ; Emit Huffman symbol for run length / number of bits + shl ecx, 4 ; temp3 = (r << 4) + nbits; + add ecx, eax + mov eax, INT [ebp + ecx * 4] ; code = actbl->ehufco[temp3]; + movzx ecx, byte [ebp + ecx + 1024] ; size = actbl->ehufsi[temp3]; + EMIT_BITS eax + + movsx edx, word [esi+DCTSIZE2*2] ; temp2 = t2[k]; + ; Mask off any extra bits in code + mov ecx, dword [esp+temp2] + mov eax, 1 + shl eax, cl + dec eax + and eax, edx ; temp2 &= (((JLONG)1)<<nbits) - 1; + EMIT_BITS eax ; PUT_BITS(temp2, nbits) + mov edx, dword [esp+temp3] + add esi, 2 ; ++k; + shr edx, 1 ; index >>= 1; + + jmp .BLOOP +.ELOOP: + movdqa xmm0, XMMWORD [esp + t1 + 32 * SIZEOF_WORD] ; __m128i tmp0 = _mm_loadu_si128((__m128i *)(t1 + 0)); + movdqa xmm1, XMMWORD [esp + t1 + 40 * SIZEOF_WORD] ; __m128i tmp1 = _mm_loadu_si128((__m128i *)(t1 + 8)); + movdqa xmm2, XMMWORD [esp + t1 + 48 * SIZEOF_WORD] ; __m128i tmp2 = _mm_loadu_si128((__m128i *)(t1 + 16)); + movdqa xmm3, XMMWORD [esp + t1 + 56 * SIZEOF_WORD] ; __m128i tmp3 = _mm_loadu_si128((__m128i *)(t1 + 24)); + pcmpeqw xmm0, xmm7 ; tmp0 = _mm_cmpeq_epi16(tmp0, zero); + pcmpeqw xmm1, xmm7 ; tmp1 = _mm_cmpeq_epi16(tmp1, zero); + pcmpeqw xmm2, xmm7 ; tmp2 = _mm_cmpeq_epi16(tmp2, zero); + pcmpeqw xmm3, xmm7 ; tmp3 = _mm_cmpeq_epi16(tmp3, zero); + packsswb xmm0, xmm1 ; tmp0 = _mm_packs_epi16(tmp0, tmp1); + packsswb xmm2, xmm3 ; tmp2 = _mm_packs_epi16(tmp2, tmp3); + pmovmskb edx, xmm0 ; index = ((uint64_t)_mm_movemask_epi8(tmp0)) << 0; + pmovmskb ecx, xmm2 ; index = ((uint64_t)_mm_movemask_epi8(tmp2)) << 16; + shl ecx, 16 + or edx, ecx + not edx ; index = ~index; + + lea eax, [esp + t1 + (DCTSIZE2/2) * 2] + sub eax, esi + shr eax, 1 + bsf ecx, edx ; r = __builtin_ctzl(index); + jz near .ELOOP2 + shr edx, cl ; index >>= r; + add ecx, eax + lea esi, [esi+ecx*2] ; k += r; + mov dword [esp+temp3], edx + jmp .BRLOOP2 +.BLOOP2: + bsf ecx, edx ; r = __builtin_ctzl(index); + jz near .ELOOP2 + lea esi, [esi+ecx*2] ; k += r; + shr edx, cl ; index >>= r; + mov dword [esp+temp3], edx +.BRLOOP2: + cmp ecx, 16 ; while (r > 15) { + jl near .ERLOOP2 + sub ecx, 16 ; r -= 16; + mov dword [esp+temp], ecx + mov eax, INT [ebp + 240 * 4] ; code_0xf0 = actbl->ehufco[0xf0]; + movzx ecx, byte [ebp + 1024 + 240] ; size_0xf0 = actbl->ehufsi[0xf0]; + EMIT_BITS eax ; EMIT_BITS(code_0xf0, size_0xf0) + mov ecx, dword [esp+temp] + jmp .BRLOOP2 +.ERLOOP2: + movsx eax, word [esi] ; temp = t1[k]; + bsr eax, eax ; nbits = 32 - __builtin_clz(temp); + inc eax + mov dword [esp+temp2], eax + ; Emit Huffman symbol for run length / number of bits + shl ecx, 4 ; temp3 = (r << 4) + nbits; + add ecx, eax + mov eax, INT [ebp + ecx * 4] ; code = actbl->ehufco[temp3]; + movzx ecx, byte [ebp + ecx + 1024] ; size = actbl->ehufsi[temp3]; + EMIT_BITS eax + + movsx edx, word [esi+DCTSIZE2*2] ; temp2 = t2[k]; + ; Mask off any extra bits in code + mov ecx, dword [esp+temp2] + mov eax, 1 + shl eax, cl + dec eax + and eax, edx ; temp2 &= (((JLONG)1)<<nbits) - 1; + EMIT_BITS eax ; PUT_BITS(temp2, nbits) + mov edx, dword [esp+temp3] + add esi, 2 ; ++k; + shr edx, 1 ; index >>= 1; + + jmp .BLOOP2 +.ELOOP2: + ; If the last coef(s) were zero, emit an end-of-block code + lea edx, [esp + t1 + (DCTSIZE2-1) * 2] ; r = DCTSIZE2-1-k; + cmp edx, esi ; if (r > 0) { + je .EFN + mov eax, INT [ebp] ; code = actbl->ehufco[0]; + movzx ecx, byte [ebp + 1024] ; size = actbl->ehufsi[0]; + EMIT_BITS eax +.EFN: + mov eax, [esp+buffer] + pop esi + ; Save put_buffer & put_bits + mov dword [esi+8], put_buffer ; state->cur.put_buffer = put_buffer; + mov dword [esi+12], put_bits ; state->cur.put_bits = put_bits; + + pop ebp + pop edi + pop esi +; pop edx ; need not be preserved + pop ecx + pop ebx + mov esp, ebp ; esp <- aligned ebp + pop esp ; esp <- original ebp + pop ebp + ret + +; For some reason, the OS X linker does not honor the request to align the +; segment unless we do this. + align 32 |