Mercurial > pub > dyncall > dyncall
view doc/disas_examples/ppc.darwin.disas @ 331:74c056b597b7
- disassembly example annotations
- callconv appendix in doc:
* ppc64 chapter
* some cleanups for consistency
author | Tassilo Philipp |
---|---|
date | Sat, 23 Nov 2019 13:51:35 +0100 |
parents | c0390dc85a07 |
children | ead041d93e36 |
line wrap: on
line source
; #include <stdlib.h> ; ; void leaf_call(int b, int c, int d, int e, int f, int g, int h) ; { ; } ; ; void nonleaf_call(int a, int b, int c, int d, int e, int f, int g, int h) ; { ; /* use some local data */ ; *(char*)alloca(220) = 'L'; ; leaf_call(b, c, d, e, f, g, h); ; } ; ; int main() ; { ; nonleaf_call(0, 1, 2, 3, 4, 5, 6, 7); ; return 0; ; } ; output from darwin-8.0.1-ppc w/ gcc 3.3 _leaf_call: 0: bf c1 ff f8 stmw 30, -8(1) 4: 94 21 ff d0 stwu 1, -48(1) 8: 7c 3e 0b 78 mr 30, 1 c: 90 7e 00 48 stw 3, 72(30) 10: 90 9e 00 4c stw 4, 76(30) 14: 90 be 00 50 stw 5, 80(30) 18: 90 de 00 54 stw 6, 84(30) 1c: 90 fe 00 58 stw 7, 88(30) 20: 91 1e 00 5c stw 8, 92(30) 24: 91 3e 00 60 stw 9, 96(30) 28: 80 21 00 00 lwz 1, 0(1) 2c: bb c1 ff f8 lmw 30, -8(1) 30: 4e 80 00 20 blr _nonleaf_call: 34: 7c 08 02 a6 mflr 0 ; | lr -> gpr0 38: bf c1 ff f8 stmw 30, -8(1) ; | store gpr{30,31} 3c: 90 01 00 08 stw 0, 8(1) ; | prolog store lr 40: 94 21 ff b0 stwu 1, -80(1) ; | open frame and store sp at top of stack 44: 7c 3e 0b 78 mr 30, 1 ; / sp -> gpr30, latter used for some fixed addressing below 48: 90 7e 00 68 stw 3, 104(30) ; \ 4c: 90 9e 00 6c stw 4, 108(30) ; | 50: 90 be 00 70 stw 5, 112(30) ; | 54: 90 de 00 74 stw 6, 116(30) ; | 58: 90 fe 00 78 stw 7, 120(30) ; | all in args -> spill area in prev frame 5c: 91 1e 00 7c stw 8, 124(30) ; | 60: 91 3e 00 80 stw 9, 128(30) ; | 64: 91 5e 00 84 stw 10, 132(30) ; | 68: 80 01 00 00 lwz 0, 0(1) ; fetch back-chain ptr (parent frame's sp) from stack of top by prolog -> gpr0, and ... 6c: 94 01 ff 10 stwu 0, -240(1) ; ... update it further up the stack for alloca(220) - with padding to guarantee alignment 70: 38 41 00 40 addi 2, 1, 64 ; | 74: 38 02 00 0f addi 0, 2, 15 ; | start of alloca()'d memory -> gpr2, by ... 78: 54 00 e1 3e srwi 0, 0, 4 ; | ... using gpr0 as helper to align to 16b, leaving at least 64b at top of stack 7c: 54 02 20 36 slwi 2, 0, 4 ; | 80: 38 00 00 4c li 0, 76 ; 'L' -> gpr0, and ... 84: 98 02 00 00 stb 0, 0(2) ; ... store in local area (of alloca()'d space) 88: 80 7e 00 6c lwz 3, 108(30) ; | 8c: 80 9e 00 70 lwz 4, 112(30) ; | 90: 80 be 00 74 lwz 5, 116(30) ; | 94: 80 de 00 78 lwz 6, 120(30) ; | arg 0,1,2,3,4,5,6 (fetched from spill area from prev frame) 98: 80 fe 00 7c lwz 7, 124(30) ; | 9c: 81 1e 00 80 lwz 8, 128(30) ; | a0: 81 3e 00 84 lwz 9, 132(30) ; | a4: 4b ff ff 5d bl .+67108700 ; call and put return address -> lr a8: 80 21 00 00 lwz 1, 0(1) ; | ac: 80 01 00 08 lwz 0, 8(1) ; | b0: 7c 08 03 a6 mtlr 0 ; | epilog b4: bb c1 ff f8 lmw 30, -8(1) ; | b8: 4e 80 00 20 blr ; | _main: bc: 7c 08 02 a6 mflr 0 ; | c0: bf c1 ff f8 stmw 30, -8(1) ; | c4: 90 01 00 08 stw 0, 8(1) ; | prolog c8: 94 21 ff b0 stwu 1, -80(1) ; | cc: 7c 3e 0b 78 mr 30, 1 ; | d0: 38 60 00 00 li 3, 0 ; arg 0 d4: 38 80 00 01 li 4, 1 ; arg 1 d8: 38 a0 00 02 li 5, 2 ; arg 2 dc: 38 c0 00 03 li 6, 3 ; arg 3 e0: 38 e0 00 04 li 7, 4 ; arg 4 e4: 39 00 00 05 li 8, 5 ; arg 5 e8: 39 20 00 06 li 9, 6 ; arg 6 ec: 39 40 00 07 li 10, 7 ; arg 7 f0: 4b ff ff 45 bl .+67108676 ; call and put return address -> lr f4: 38 00 00 00 li 0, 0 ; return value (pointlessly) via gpr0 ... f8: 7c 03 03 78 mr 3, 0 ; ... to gpr3 fc: 80 21 00 00 lwz 1, 0(1) ; | 100: 80 01 00 08 lwz 0, 8(1) ; | 104: 7c 08 03 a6 mtlr 0 ; | epilog 108: bb c1 ff f8 lmw 30, -8(1) ; | 10c: 4e 80 00 20 blr ; | ; ------------- more than 8 int args -----------> ; #include <stdlib.h> ; ; void leaf_call(int b, int c, int d, int e, int f, int g, int h, int i, int j) ; { ; } ; ; void nonleaf_call(int a, int b, int c, int d, int e, int f, int g, int h, int i, int j) ; { ; /* use some local data */ ; *(char*)alloca(220) = 'L'; ; leaf_call(b, c, d, e, f, g, h, i, j); ; } ; ; int main() ; { ; nonleaf_call(0, 1, 2, 3, 4, 5, 6, 7, 8, 9); ; return 0; ; } ; output from darwin-8.0.1-ppc w/ gcc 3.3 _leaf_call: 0: bf c1 ff f8 stmw 30, -8(1) 4: 94 21 ff d0 stwu 1, -48(1) 8: 7c 3e 0b 78 mr 30, 1 c: 90 7e 00 48 stw 3, 72(30) 10: 90 9e 00 4c stw 4, 76(30) 14: 90 be 00 50 stw 5, 80(30) 18: 90 de 00 54 stw 6, 84(30) 1c: 90 fe 00 58 stw 7, 88(30) 20: 91 1e 00 5c stw 8, 92(30) 24: 91 3e 00 60 stw 9, 96(30) 28: 91 5e 00 64 stw 10, 100(30) 2c: 80 21 00 00 lwz 1, 0(1) 30: bb c1 ff f8 lmw 30, -8(1) 34: 4e 80 00 20 blr _nonleaf_call: 38: 7c 08 02 a6 mflr 0 ; | 3c: bf c1 ff f8 stmw 30, -8(1) ; | 40: 90 01 00 08 stw 0, 8(1) ; | prolog 44: 94 21 ff a0 stwu 1, -96(1) ; | 48: 7c 3e 0b 78 mr 30, 1 ; / 4c: 90 7e 00 78 stw 3, 120(30) ; \ 50: 90 9e 00 7c stw 4, 124(30) ; | 54: 90 be 00 80 stw 5, 128(30) ; | 58: 90 de 00 84 stw 6, 132(30) ; | 5c: 90 fe 00 88 stw 7, 136(30) ; | in args 0,1,2,3,4,5,6,7 -> spill area in prev frame 60: 91 1e 00 8c stw 8, 140(30) ; | 64: 91 3e 00 90 stw 9, 144(30) ; | 68: 91 5e 00 94 stw 10, 148(30) ; | 6c: 80 01 00 00 lwz 0, 0(1) ; fetch back-chain ptr (parent frame's sp) from stack of top by prolog -> gpr0, and ... 70: 94 01 ff 10 stwu 0, -240(1) ; ... update it further up the stack for alloca(220) - with padding to guarantee alignment 74: 38 41 00 50 addi 2, 1, 80 ; | 78: 38 02 00 0f addi 0, 2, 15 ; | start of alloca()'d memory -> gpr2, by ... 7c: 54 00 e1 3e srwi 0, 0, 4 ; | ... using gpr0 as helper to align to 16b, leaving at least 64b at top of stack 80: 54 02 20 36 slwi 2, 0, 4 ; | 84: 38 00 00 4c li 0, 76 ; 'L' -> gpr0, and ... 88: 98 02 00 00 stb 0, 0(2) ; ... store in local area (of alloca()'d space) 8c: 80 1e 00 9c lwz 0, 156(30) ; arg 7 (fetched from stack param area from prev frame), and ... 90: 90 01 00 38 stw 0, 56(1) ; ... "pushed" onto stack 94: 80 7e 00 7c lwz 3, 124(30) ; | 98: 80 9e 00 80 lwz 4, 128(30) ; | 9c: 80 be 00 84 lwz 5, 132(30) ; | a0: 80 de 00 88 lwz 6, 136(30) ; | arg 0,1,2,3,4,5,6 (fetched from spill area from prev frame) a4: 80 fe 00 8c lwz 7, 140(30) ; | a8: 81 1e 00 90 lwz 8, 144(30) ; | ac: 81 3e 00 94 lwz 9, 148(30) ; | b0: 81 5e 00 98 lwz 10, 152(30) ; arg 7 (fetched from stack param area from prev frame) b4: 4b ff ff 4d bl .+67108684 ; call and put return address -> lr b8: 80 21 00 00 lwz 1, 0(1) ; | bc: 80 01 00 08 lwz 0, 8(1) ; | c0: 7c 08 03 a6 mtlr 0 ; | epilog c4: bb c1 ff f8 lmw 30, -8(1) ; | c8: 4e 80 00 20 blr ; | _main: cc: 7c 08 02 a6 mflr 0 ; | d0: bf c1 ff f8 stmw 30, -8(1) ; | d4: 90 01 00 08 stw 0, 8(1) ; | prolog d8: 94 21 ff a0 stwu 1, -96(1) ; | dc: 7c 3e 0b 78 mr 30, 1 ; | e0: 38 00 00 08 li 0, 8 ; arg 8, ... e4: 90 01 00 38 stw 0, 56(1) ; ... "pushed" onto stack e8: 38 00 00 09 li 0, 9 ; arg 9, ... ec: 90 01 00 3c stw 0, 60(1) ; ... "pushed" onto stack f0: 38 60 00 00 li 3, 0 ; arg 0 f4: 38 80 00 01 li 4, 1 ; arg 1 f8: 38 a0 00 02 li 5, 2 ; arg 2 fc: 38 c0 00 03 li 6, 3 ; arg 3 100: 38 e0 00 04 li 7, 4 ; arg 4 104: 39 00 00 05 li 8, 5 ; arg 5 108: 39 20 00 06 li 9, 6 ; arg 6 10c: 39 40 00 07 li 10, 7 ; arg 7 110: 4b ff ff 29 bl .+67108648 ; call and put return address -> lr 114: 38 00 00 00 li 0, 0 ; return value (pointlessly) via gpr0 ... 118: 7c 03 03 78 mr 3, 0 ; ... to gpr3 11c: 80 21 00 00 lwz 1, 0(1) ; | 120: 80 01 00 08 lwz 0, 8(1) ; | 124: 7c 08 03 a6 mtlr 0 ; | epilog 128: bb c1 ff f8 lmw 30, -8(1) ; | 12c: 4e 80 00 20 blr ; | ; ------------- var args with ints and floats to see spilling (which remains only int regs), b/c doubles are passed via them and floats are promoted to doubles in (...) -----------> ; #include <stdlib.h> ; #include <stdarg.h> ; ; void leaf_call(int b, int c, int d, int e, float f, float g, int h, int i, float j) ; { ; } ; ; void nonleaf_call(int a, ...) ; { ; int b, c, d, e, h, i; ; float f, g, j; ; va_list ap; ; va_start(ap, a); ; b = va_arg(ap, int); ; c = va_arg(ap, int); ; d = va_arg(ap, int); ; e = va_arg(ap, int); ; f = (float)va_arg(ap, double); ; g = (float)va_arg(ap, double); ; h = va_arg(ap, int); ; i = va_arg(ap, int); ; j = (float)va_arg(ap, double); ; /* use some local data */ ; *(char*)alloca(220) = 'L'; ; leaf_call(b, c, d, e, f, g, h, i, j); ; } ; ; int main() ; { ; nonleaf_call(0, 1, 2, 3, 4, 5.f, 6.f, 7, 8, 9.f); ; return 0; ; } ; output from darwin-8.0.1-ppc w/ gcc 3.3 _leaf_call: 0: bf c1 ff f8 stmw 30, -8(1) 4: 94 21 ff d0 stwu 1, -48(1) 8: 7c 3e 0b 78 mr 30, 1 c: 90 7e 00 48 stw 3, 72(30) 10: 90 9e 00 4c stw 4, 76(30) 14: 90 be 00 50 stw 5, 80(30) 18: 90 de 00 54 stw 6, 84(30) 1c: d0 3e 00 58 stfs 1, 88(30) 20: d0 5e 00 5c stfs 2, 92(30) 24: 91 3e 00 60 stw 9, 96(30) 28: 91 5e 00 64 stw 10, 100(30) 2c: d0 7e 00 68 stfs 3, 104(30) 30: 80 21 00 00 lwz 1, 0(1) 34: bb c1 ff f8 lmw 30, -8(1) 38: 4e 80 00 20 blr _nonleaf_call: 3c: 7c 08 02 a6 mflr 0 ; | 40: bf c1 ff f8 stmw 30, -8(1) ; | 44: 90 01 00 08 stw 0, 8(1) ; | prolog 48: 94 21 ff 70 stwu 1, -144(1) ; | 4c: 7c 3e 0b 78 mr 30, 1 ; / 50: 90 9e 00 ac stw 4, 172(30) ; \ 54: 90 be 00 b0 stw 5, 176(30) ; | 58: 90 de 00 b4 stw 6, 180(30) ; | 5c: 90 fe 00 b8 stw 7, 184(30) ; | 60: 91 1e 00 bc stw 8, 188(30) ; | in args ,1,2,3,4,5,6,7 -> spill area in prev frame 64: 91 3e 00 c0 stw 9, 192(30) ; | 68: 91 5e 00 c4 stw 10, 196(30) ; | 6c: 90 7e 00 a8 stw 3, 168(30) ; | <- this is in arg 0, the only named arg 70: 38 1e 00 ac addi 0, 30, 172 ; get pointer to first unnamed arg in gpr0 for vararg iteration, ... 74: 90 1e 00 74 stw 0, 116(30) ; ... and store read ptr in local area 78: 81 3e 00 74 lwz 9, 116(30) ; \ read ptr -> gpr0 7c: 80 5e 00 74 lwz 2, 116(30) ; | use gpr2 as helper ... 80: 38 02 00 04 addi 0, 2, 4 ; | ... to increment read ptr ... 84: 90 1e 00 74 stw 0, 116(30) ; | in arg 1 ... and restore 88: 80 09 00 00 lwz 0, 0(9) ; | load in arg 1, and ... 8c: 90 1e 00 50 stw 0, 80(30) ; / ... store in temp space in local area 90: 81 3e 00 74 lwz 9, 116(30) ; \ 94: 80 5e 00 74 lwz 2, 116(30) ; | 98: 38 02 00 04 addi 0, 2, 4 ; | 9c: 90 1e 00 74 stw 0, 116(30) ; | in arg 2 a0: 80 09 00 00 lwz 0, 0(9) ; | a4: 90 1e 00 54 stw 0, 84(30) ; / a8: 81 3e 00 74 lwz 9, 116(30) ; \ ac: 80 5e 00 74 lwz 2, 116(30) ; | b0: 38 02 00 04 addi 0, 2, 4 ; | b4: 90 1e 00 74 stw 0, 116(30) ; | in arg 3 b8: 80 09 00 00 lwz 0, 0(9) ; | bc: 90 1e 00 58 stw 0, 88(30) ; / c0: 81 3e 00 74 lwz 9, 116(30) ; \ c4: 80 5e 00 74 lwz 2, 116(30) ; | c8: 38 02 00 04 addi 0, 2, 4 ; | cc: 90 1e 00 74 stw 0, 116(30) ; | in arg 4 d0: 80 09 00 00 lwz 0, 0(9) ; | d4: 90 1e 00 5c stw 0, 92(30) ; / d8: 81 3e 00 74 lwz 9, 116(30) ; \ dc: 80 5e 00 74 lwz 2, 116(30) ; | e0: 38 02 00 08 addi 0, 2, 8 ; | e4: 90 1e 00 74 stw 0, 116(30) ; | in arg 5 (float, promoted to double) e8: c8 09 00 00 lfd 0, 0(9) ; | ec: fc 00 00 18 frsp 0, 0 ; | f0: d0 1e 00 68 stfs 0, 104(30) ; / f4: 81 3e 00 74 lwz 9, 116(30) ; \ f8: 80 5e 00 74 lwz 2, 116(30) ; | fc: 38 02 00 08 addi 0, 2, 8 ; | 100: 90 1e 00 74 stw 0, 116(30) ; | in arg 6 (float, promoted to double) 104: c8 09 00 00 lfd 0, 0(9) ; | 108: fc 00 00 18 frsp 0, 0 ; | 10c: d0 1e 00 6c stfs 0, 108(30) ; / 110: 81 3e 00 74 lwz 9, 116(30) ; \ 114: 80 5e 00 74 lwz 2, 116(30) ; | 118: 38 02 00 04 addi 0, 2, 4 ; | 11c: 90 1e 00 74 stw 0, 116(30) ; | in arg 7 120: 80 09 00 00 lwz 0, 0(9) ; | 124: 90 1e 00 60 stw 0, 96(30) ; / 128: 81 3e 00 74 lwz 9, 116(30) ; \ 12c: 80 5e 00 74 lwz 2, 116(30) ; | 130: 38 02 00 04 addi 0, 2, 4 ; | 134: 90 1e 00 74 stw 0, 116(30) ; | in arg 8 138: 80 09 00 00 lwz 0, 0(9) ; | 13c: 90 1e 00 64 stw 0, 100(30) ; / 140: 81 3e 00 74 lwz 9, 116(30) ; \ 144: 80 5e 00 74 lwz 2, 116(30) ; | 148: 38 02 00 08 addi 0, 2, 8 ; | 14c: 90 1e 00 74 stw 0, 116(30) ; | in arg 9 (float, promoted to double) 150: c8 09 00 00 lfd 0, 0(9) ; | 154: fc 00 00 18 frsp 0, 0 ; | 158: d0 1e 00 70 stfs 0, 112(30) ; / 15c: 80 01 00 00 lwz 0, 0(1) ; fetch back-chain ptr (parent frame's sp) from stack of top by prolog -> gpr0, and ... 160: 94 01 ff 10 stwu 0, -240(1) ; ... update it further up the stack for alloca 164: 38 41 00 50 addi 2, 1, 80 ; | 168: 38 02 00 0f addi 0, 2, 15 ; | start of alloca()'d memory -> gpr2, by ... 16c: 54 00 e1 3e srwi 0, 0, 4 ; | ... using gpr0 as helper to align to 16b, l 170: 54 02 20 36 slwi 2, 0, 4 ; | 174: 38 00 00 4c li 0, 76 ; 'L' -> gpr0, and ... 178: 98 02 00 00 stb 0, 0(2) ; ... store in local area (of alloca()'d space) 17c: 80 7e 00 50 lwz 3, 80(30) ; arg 0 180: 80 9e 00 54 lwz 4, 84(30) ; arg 1 184: 80 be 00 58 lwz 5, 88(30) ; arg 2 188: 80 de 00 5c lwz 6, 92(30) ; arg 3 18c: c0 3e 00 68 lfs 1, 104(30) ; arg 4 (float) 190: c0 5e 00 6c lfs 2, 108(30) ; arg 5 (float) 194: 81 3e 00 60 lwz 9, 96(30) ; arg 6 198: 81 5e 00 64 lwz 10, 100(30) ; arg 7 19c: c0 7e 00 70 lfs 3, 112(30) ; arg 8 (float) 1a0: 4b ff fe 61 bl .+67108448 ; call and put return address -> lr 1a4: 80 21 00 00 lwz 1, 0(1) ; | 1a8: 80 01 00 08 lwz 0, 8(1) ; | 1ac: 7c 08 03 a6 mtlr 0 ; | epilog 1b0: bb c1 ff f8 lmw 30, -8(1) ; | 1b4: 4e 80 00 20 blr ; | _main: 1b8: 7c 08 02 a6 mflr 0 ; | 1bc: bf c1 ff f8 stmw 30, -8(1) ; | 1c0: 90 01 00 08 stw 0, 8(1) ; | prolog 1c4: 94 21 ff 90 stwu 1, -112(1) ; | 1c8: 7c 3e 0b 78 mr 30, 1 ; | 1cc: 42 9f 00 05 bcl 20, 31, .+4 ; ppc way to get PC in ... 1d0: 7f e8 02 a6 mflr 31 ; ... gpr31 1d4: 38 00 00 07 li 0, 7 ; arg 7, ... 1d8: 90 01 00 3c stw 0, 60(1) ; ... "pushed" onto stack 1dc: 38 00 00 08 li 0, 8 ; arg 8, ... 1e0: 90 01 00 40 stw 0, 64(1) ; ... "pushed" onto stack 1e4: 3c 40 40 22 lis 2, 16418 ; | arg 9, top-half (double b/c of vararg), and ... 1e8: 38 60 00 00 li 3, 0 ; | ... bottom-half ... 1ec: 90 41 00 44 stw 2, 68(1) ; | ... "pushed" into stack 1f0: 90 61 00 48 stw 3, 72(1) ; | " 1f4: 38 00 00 00 li 0, 0 ; arg 6, bottom-half, ... 1f8: 90 01 00 38 stw 0, 56(1) ; ... "pushed" onto stack (first word in param area, top-half passed via gpr10, see below) 1fc: 38 60 00 00 li 3, 0 ; arg 0 200: 38 80 00 01 li 4, 1 ; arg 1 204: 38 a0 00 02 li 5, 2 ; arg 2 208: 38 c0 00 03 li 6, 3 ; arg 3 20c: 38 e0 00 04 li 7, 4 ; arg 4 210: 3d 20 40 14 lis 9, 16404 ; | prep arg 5 (double b/c of vararg) for move to arg reg later: top-half -> gpr9 214: 39 40 00 00 li 10, 0 ; | bottom-half -> gpr10 218: 3c 5f 00 00 addis 2, 31, 0 ; PC -> gpr2, to ... 21c: c8 02 00 98 lfd 0, 152(2) ; ... load some static data (arg 5, the float) stored right after this function -> gpr0 220: 7d 28 4b 78 mr 8, 9 ; arg 5, top-half 224: 7d 49 53 78 mr 9, 10 ; arg 5, bottom-half 228: fc 20 00 90 fmr 1, 0 ; arg 5 in 1st fp reg 22c: 3d 60 40 18 lis 11, 16408 ; | prep arg 6 (double b/c of vararg) for move to arg reg later: top-half -> gpr11 230: 39 80 00 00 li 12, 0 ; | bottom-half -> gpr12 (this one is pointless, unused, bottom-half already placed on stack) 234: 3c 5f 00 00 addis 2, 31, 0 ; PC -> gpr2, to ... 238: c8 02 00 a0 lfd 0, 160(2) ; ... load some static data (arg 6, the 2nd float) stored right after this function -> gpr0 23c: 7d 6a 5b 78 mr 10, 11 ; arg 6, top-half 240: fc 40 00 90 fmr 2, 0 ; arg 5 in 2nd fp reg 244: c8 01 00 44 lfd 0, 68(1) ; arg 9, ... 248: fc 60 00 90 fmr 3, 0 ; ... -> 3rd fp reg 24c: 4b ff fd f1 bl .+67108336 ; call and put return address -> lr 250: 7c 03 03 78 mr 3, 0 ; return value @@@unsure why gpr0 is guaranteed to be 0 here 254: 80 21 00 00 lwz 1, 0(1) ; | 258: 80 01 00 08 lwz 0, 8(1) ; | 25c: 7c 08 03 a6 mtlr 0 ; | epilog 260: bb c1 ff f8 lmw 30, -8(1) ; | 264: 4e 80 00 20 blr ; | ; vim: ft=asm