From 95b482d5d5ea91ad251f3879f04debae73c2baa6 Mon Sep 17 00:00:00 2001 From: Bruce Mitchener Date: Thu, 21 Jan 2021 15:27:31 +0700 Subject: [PATCH] Use gcc / clang overflow builtins. (#142) * Use gcc / clang overflow builtins. This avoids expensive checks for overflow that employ undefined behavior. This is a step along the way towards replacing the old hand-written assembler that did the same thing in terms of using the CPU's overflow detection. * Remove unimplemented SPARC asm for multiplication, divide, and remainder. This wasn't implemented before, and for multiplication, it is now implemented for gcc and friends using overflow detection. * Remove USE_INLINE_ARITH. Now that we have the compiler built-ins for detecting overflow, we don't need custom assembly for it for each platform. For now, we keep, but still don't use, the code that do a hot path through the dispatch loop for some math. This code isn't actually running or in use, but it is separate from how the other inline arithmetic was being performed. These are the `fast_op_*` functions that are implemented in assembler. --- CMakeLists.txt | 1 - inc/arith.h | 42 --------------- inc/arith2.h | 140 ------------------------------------------------ inc/lispemul.h | 4 -- inc/version.h | 20 +++---- src/arith2.c | 80 +++++++++++++-------------- src/arith4.c | 61 ++++++--------------- src/dsp386.il | 48 ----------------- src/dspSPARC.il | 74 ------------------------- 9 files changed, 63 insertions(+), 407 deletions(-) delete mode 100644 inc/arith2.h diff --git a/CMakeLists.txt b/CMakeLists.txt index d9810a9..5950566 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -228,7 +228,6 @@ SET(MAIKO_HDRS inc/adr68k.h inc/allocmdsdefs.h inc/arith2defs.h - inc/arith2.h inc/arith3defs.h inc/arith4defs.h inc/arith.h diff --git a/inc/arith.h b/inc/arith.h index d4d93b5..f87c5f5 100644 --- a/inc/arith.h +++ b/inc/arith.h @@ -154,29 +154,6 @@ } - /* Used in ISC asm inlines in arithmetic, to defeat optimizer. - with INLINE_ERROR_EXIT, we use asm jumps to avoid having - one or the other eliminated as dead code. */ -#ifdef ISC -#define INLINE_ARITH_SWITCH(arg,retlbl) \ - switch(arg & 0xFFFF0000){ \ - case 0: \ - result=(S_POSITIVE | arg); \ - break; \ - case 0xFFFF0000: \ - result=(S_NEGATIVE | (0xFFFF & arg)); \ - break; \ - default:{register LispPTR *wordp; \ - /* arg is FIXP, call createcell */ \ - wordp = (LispPTR *) createcell68k(TYPE_FIXP); \ - *((int *)wordp) = arg; \ - result=(LADDR_from_68k(wordp)); \ - } \ - } \ - asm("jmp " retlbl) -#endif /* ISC */ - - #define N_IARITH_BODY_2(a, tos, op) \ { \ register int arg1,arg2; \ @@ -220,23 +197,4 @@ do_ufn: ERROR_EXIT(a); \ } - - - -#ifdef I386 - - /*********************************************************/ - /* */ - /* Macros for arithmetic operations, to let inline work */ - /* */ - /*********************************************************/ - -#define iplus32(a,b) Xiplus32() -#define plus32(a,b) Xplus32() -#define iplus32n(a,b) Xiplus32n() -#define sub32(a,b) Xsub32() -#define isub32(a,b) Xisub32() -#define sub32n(a,b) Xisub32n() -#endif - #endif /* ARITH_H */ diff --git a/inc/arith2.h b/inc/arith2.h deleted file mode 100644 index 1c10d1e..0000000 --- a/inc/arith2.h +++ /dev/null @@ -1,140 +0,0 @@ -#ifndef ARITH2_H -#define ARITH2_H 1 -/* $Id: arith2.h,v 1.2 1999/01/03 02:05:52 sybalsky Exp $ (C) Copyright Venue, All Rights Reserved */ - - - -/************************************************************************/ -/* */ -/* (C) Copyright 1989-92 Venue. All Rights Reserved. */ -/* Manufactured in the United States of America. */ -/* */ -/************************************************************************/ - - -/************************************************************************/ -/* */ -/* Take care of results for inlined arithmetic cases. */ -/* xxx_RESULT does overflow checking and boxing. */ -/* */ -/* */ -/************************************************************************/ -#ifdef ARITHINLINE -#ifdef GCC386 -/* Inline defines for arith on GCC386 machines */ - - -extern inline const int plus32 (int arg1, int arg2) -{ - asm(" addl %2,%0 \n\ - jo plus_err": "=r" (arg2): "0" (arg2), "r" (arg1)); - return arg2; -} -#define PLUS_RESULT \ - INLINE_ARITH_SWITCH(result,"plus_ret"); \ - asm("plus_err:"); \ - INLINE_ERROR_EXIT(tos,"plus_ret") - - - -extern inline const int iplus32 (int arg1, int arg2) -{ - asm(" addl %2,%0 \n\ - jo iplus_err": "=r" (arg2): "0" (arg2), "r" (arg1)); - return arg2; -} -#define IPLUS_RESULT \ - INLINE_ARITH_SWITCH(result,"iplus_ret"); \ - asm("iplus_err:"); \ - INLINE_ERROR_EXIT(tos,"iplus_ret") - - - -extern inline const int sub32 (int arg1, int arg2) -{ - asm("subl %2,%0 \n\ - jo diff_err": "=r" (arg1): "0" (arg1), "r" (arg2)); - return arg1; -} -#define DIFF_RESULT \ - INLINE_ARITH_SWITCH(result,"diff_ret"); \ - asm("diff_err:"); \ - INLINE_ERROR_EXIT(tos,"diff_ret") - - - -extern inline const int isub32 (int arg1, int arg2) -{ - asm(" subl %2,%0 \n\ - jo idiff_err": "=r" (arg1): "0" (arg1), "r" (arg2)); - return arg1; -} -#define IDIFF_RESULT \ - INLINE_ARITH_SWITCH(result,"idiff_ret"); \ - asm("idiff_err:"); \ - INLINE_ERROR_EXIT(tos,"idiff_ret") - - - -extern inline const int iplus32n(int arg1, int arg2) -{ - asm("addl %2,%0 \n\ - jo iplusn_err": "=r" (arg2): "0" (arg2), "r" (arg1)); - return arg2; -} -#define IPLUSN_RESULT \ - INLINE_ARITH_SWITCH(result,"iplusn_ret"); \ - asm("iplusn_err:"); \ - INLINE_ERROR_EXIT(tos,"iplusn_ret") - - - -extern inline const int sub32n (int arg1, int arg2) -{ - asm(" subl %2,%0 \n\ - jo idiffn_err": "=r" (arg1): "0" (arg1), "r" (arg2)); - return arg1; -} -#define IDIFFN_RESULT \ - INLINE_ARITH_SWITCH(result,"idiffn_ret"); \ - asm("idiffn_err:"); \ - INLINE_ERROR_EXIT(tos,"idiffn_ret") - - -#else /* Any other ARITHINLINE case */ - -#define PLUS_RESULT \ - N_ARITH_SWITCH(result); \ -doufn2: plus_err_label(); \ - ERROR_EXIT(tos); - - -#define IPLUS_RESULT \ - N_ARITH_SWITCH(result); \ -dummy: iplus_err_label(); - - -#define DIFF_RESULT \ - N_ARITH_SWITCH(result); \ -doufn2: diff_err_label(); \ - ERROR_EXIT(tos); - - -#define IDIFF_RESULT \ - N_ARITH_SWITCH(result); \ -dummy: idiff_err_label(); - - -#define IPLUSN_RESULT \ - N_ARITH_SWITCH(result); \ -dummy: iplusn_err_label(); - - -#define IDIFFN_RESULT \ - N_ARITH_SWITCH(result); \ -dummy: idiffn_err_label(); - -#endif /* GCC386 */ -#endif /* ARITHINLINE */ - -#endif /* ARITH2_H */ diff --git a/inc/lispemul.h b/inc/lispemul.h index 1a08725..c35638a 100644 --- a/inc/lispemul.h +++ b/inc/lispemul.h @@ -483,10 +483,6 @@ DOSTACKOVERFLOW(argnum,bytenum) if it needs hardreturn-cleanup /************************************************************************/ #define ERROR_EXIT(tos) {TopOfStack=tos; Error_Exit = 1; return(-1);} -#ifdef ISC -#define INLINE_ERROR_EXIT(tos,retlbl) {TopOfStack=tos; Error_Exit=1 asm("movl $-1,%0\n" retlbl ":" : "=g" (result) : "0" (result)); return(result); } -#endif - #define TIMER_EXIT(tos) {TopOfStack=tos; Error_Exit = 1; return(-2);} diff --git a/inc/version.h b/inc/version.h index 2210c03..bfe1582 100644 --- a/inc/version.h +++ b/inc/version.h @@ -170,7 +170,6 @@ error Must specify RELEASE to build Medley. /* */ /* Defaults: Unaligned fetches OK UNALIGNED_FETCH_OK */ /* fp values used with */ - /* Use asm inline arith USE_INLINE_ARITH */ /* pointer-wide unsigned UNSIGNED */ /* pointer-wide int INT */ /* */ @@ -192,12 +191,10 @@ error Must specify RELEASE to build Medley. #ifdef SUN3_OS3_IL #define SUN3_OS3_OR_OS4_IL 1 -#define USE_INLINE_ARITH 1 #endif #ifdef SUN3_OS4_IL #define SUN3_OS3_OR_OS4_IL 1 -#define USE_INLINE_ARITH 1 #endif @@ -220,6 +217,16 @@ error Must specify RELEASE to build Medley. + /********************************************************/ + /* */ + /********************************************************/ +#ifdef __GNUC__ +#define USE_OVERFLOW_BUILTINS +#endif + + + + /********************************************************/ /* */ /********************************************************/ @@ -232,13 +239,6 @@ error Must specify RELEASE to build Medley. - /********************************************************/ - /* */ - /********************************************************/ -#ifdef I386 -#define USE_INLINE_ARITH 1 -#endif /* I386 */ - /********************************************************/ /* */ /********************************************************/ diff --git a/src/arith2.c b/src/arith2.c index abec5dc..3f8e950 100644 --- a/src/arith2.c +++ b/src/arith2.c @@ -31,28 +31,26 @@ N_OP_plus2 ************************************************************/ LispPTR N_OP_plus2(int tosm1, int tos) { - register int arg1, arg2; - register int result; + int arg1, arg2; + int result; N_GETNUMBER(tos, arg1, doufn); N_GETNUMBER(tosm1, arg2, doufn); -#ifdef USE_INLINE_ARITH +#ifdef USE_OVERFLOW_BUILTINS - result = plus32(arg1, arg2); + if (__builtin_sadd_overflow(arg1, arg2, &result)) { + ERROR_EXIT(tos); + } N_ARITH_SWITCH(result); -doufn2: - plus_err_label(); - ERROR_EXIT(tos); - #else /* UB: signed integer overflow: 2147483647 + 2147483647 cannot be represented in type 'int' */ result = arg1 + arg2; if (((arg1 >= 0) == (arg2 >= 0)) && ((result >= 0) != (arg1 >= 0))) { ERROR_EXIT(tos); } N_ARITH_SWITCH(result); -#endif /* USE_INLINE_ARITH */ +#endif doufn: return (N_OP_fplus2(tosm1, tos)); @@ -68,18 +66,18 @@ doufn: /************************************************************************/ LispPTR N_OP_iplus2(int tosm1, int tos) { - register int arg1, arg2; - register int result; + int arg1, arg2; + int result; N_IGETNUMBER(tos, arg1, doufn); N_IGETNUMBER(tosm1, arg2, doufn); -#ifdef USE_INLINE_ARITH +#ifdef USE_OVERFLOW_BUILTINS - result = iplus32(arg1, arg2); + if (__builtin_sadd_overflow(arg1, arg2, &result)) { + ERROR_EXIT(tos); + } N_ARITH_SWITCH(result); -dummy: - iplus_err_label(); #else @@ -88,7 +86,7 @@ dummy: if (((arg1 >= 0) == (arg2 >= 0)) && ((result >= 0) != (arg1 >= 0))) { ERROR_EXIT(tos); } N_ARITH_SWITCH(result); -#endif /* USE_INLINE_ARITH */ +#endif doufn: ERROR_EXIT(tos); @@ -102,21 +100,19 @@ N_OP_difference ************************************************************/ LispPTR N_OP_difference(int tosm1, int tos) { - register int arg1, arg2; - register int result; + int arg1, arg2; + int result; N_GETNUMBER(tosm1, arg1, doufn); N_GETNUMBER(tos, arg2, doufn); -#ifdef USE_INLINE_ARITH +#ifdef USE_OVERFLOW_BUILTINS - result = sub32(arg1, arg2); + if (__builtin_ssub_overflow(arg1, arg2, &result)) { + ERROR_EXIT(tos); + } N_ARITH_SWITCH(result); -doufn2: - diff_err_label(); - ERROR_EXIT(tos); - #else /* UB: signed integer overflow: -2147483647 - 320 cannot be represented in type 'int' */ @@ -131,18 +127,18 @@ doufn: } LispPTR N_OP_idifference(int tosm1, int tos) { - register int arg1, arg2; - register int result; + int arg1, arg2; + int result; N_IGETNUMBER(tosm1, arg1, doufn); N_IGETNUMBER(tos, arg2, doufn); -#ifdef USE_INLINE_ARITH +#ifdef USE_OVERFLOW_BUILTINS - result = isub32(arg1, arg2); + if (__builtin_ssub_overflow(arg1, arg2, &result)) { + ERROR_EXIT(tos); + } N_ARITH_SWITCH(result); -dummy: - idiff_err_label(); #else /* UB: signed integer overflow: -2147483647 - 100 cannot be represented in type 'int' */ @@ -220,17 +216,17 @@ N_OP_iplusn return(tos + n) ************************************************************/ LispPTR N_OP_iplusn(int tos, int n) { - register int arg1; - register int result; + int arg1; + int result; N_IGETNUMBER(tos, arg1, do_ufn); -#ifdef USE_INLINE_ARITH +#ifdef USE_OVERFLOW_BUILTINS - result = iplus32n(arg1, n); + if (__builtin_sadd_overflow(arg1, n, &result)) { + ERROR_EXIT(tos); + } N_ARITH_SWITCH(result); -dummy: - iplusn_err_label(); #else @@ -250,17 +246,17 @@ N_OP_idifferencen return(tos - n) ************************************************************/ LispPTR N_OP_idifferencen(int tos, int n) { - register int arg1; - register int result; + int arg1; + int result; N_IGETNUMBER(tos, arg1, do_ufn); -#ifdef USE_INLINE_ARITH +#ifdef USE_OVERFLOW_BUILTINS - result = sub32n(arg1, n); + if (__builtin_ssub_overflow(arg1, n, &result)) { + ERROR_EXIT(tos); + } N_ARITH_SWITCH(result); -dummy: - idiffn_err_label(); #else diff --git a/src/arith4.c b/src/arith4.c index ce1474b..730539d 100644 --- a/src/arith4.c +++ b/src/arith4.c @@ -44,18 +44,18 @@ */ /**********************************************************************/ int N_OP_times2(int tosm1, int tos) { - register int arg1, arg2; - register int result; + int arg1, arg2; + int result; N_GETNUMBER(tosm1, arg1, doufn); N_GETNUMBER(tos, arg2, doufn); -#ifdef SUN3_OS3_OR_OS4_IL +#ifdef USE_OVERFLOW_BUILTINS - result = mpy32(arg1, arg2); + if (__builtin_smul_overflow(arg1, arg2, &result)) { + goto doufn2; + } N_ARITH_SWITCH(result); -dummy: - mpy_err_label(); #else @@ -73,18 +73,18 @@ doufn: } /* end N_OP_times2 */ int N_OP_itimes2(int tosm1, int tos) { - register int arg1, arg2; - register int result; + int arg1, arg2; + int result; N_IGETNUMBER(tosm1, arg1, doufn); N_IGETNUMBER(tos, arg2, doufn); -#ifdef SUN3_OS3_OR_OS4_IL +#ifdef USE_OVERFLOW_BUILTINS - result = impy32(arg1, arg2); + if (__builtin_smul_overflow(arg1, arg2, &result)) { + goto doufn; + } N_ARITH_SWITCH(result); -dummy: - impy_err_label(); #else @@ -108,25 +108,16 @@ doufn: */ /**********************************************************************/ int N_OP_quot(int tosm1, int tos) { - register int arg1, arg2; - register int result; + int arg1, arg2; + int result; N_GETNUMBER(tosm1, arg1, doufn); N_GETNUMBER(tos, arg2, doufn); if (arg2 == 0) goto doufn2; -#ifdef SUN3_OS3_OR_OS4_IL - - result = quot32(arg1, arg2); - N_ARITH_SWITCH(result); -dummy: - quot_err_label(); - -#else - result = arg1 / arg2; /* lmm: note: no error case!! */ N_ARITH_SWITCH(result); -#endif + doufn2: ERROR_EXIT(tos); doufn: @@ -142,20 +133,9 @@ int N_OP_iquot(int tosm1, int tos) { N_IGETNUMBER(tos, arg2, doufn); if (arg2 == 0) goto doufn; -#ifdef SUN3_OS3_OR_OS4_IL - - result = iquot32(arg1, arg2); - N_ARITH_SWITCH(result); -dummy: - iquot_err_label(); - -#else - result = arg1 / arg2; N_ARITH_SWITCH(result); -#endif - doufn: ERROR_EXIT(tos); @@ -177,20 +157,9 @@ int N_OP_iremainder(int tosm1, int tos) { N_IGETNUMBER(tos, arg2, doufn); if (arg2 == 0) goto doufn; -#ifdef SUN3_OS3_OR_OS4_IL - - result = irem32(arg1, arg2); - N_ARITH_SWITCH(result); -dummy: - irem_err_label(); - -#else - result = arg1 % arg2; N_ARITH_SWITCH(result); -#endif - doufn: ERROR_EXIT(tos); diff --git a/src/dsp386.il b/src/dsp386.il index 2eabb20..b6a42c7 100755 --- a/src/dsp386.il +++ b/src/dsp386.il @@ -142,54 +142,6 @@ jmp *optable(,%eax,4) .end - - ///////////////////////////// - // - // Arithmetic code speedups - // - // Assume edi & esi are arguments - // - // ebx is result. - // - //////////////////////////////// - -.inline Xiplus32,0 - addl %edi,%esi - jo iplus_err - movl %esi,%eax -.end - -.inline Xiplus32n,0 - leal (%edi),%eax - addl %esi,%eax - jo iplusn_err -.end - - -.inline Xplus32,0 - leal (%edi),%eax - addl %esi,%eax - jo plus_err -.end - -.inline Xsub32,0 - leal (%edi),%eax - subl %esi,%eax - jo diff_err -.end - -.inline Xisub32,0 - leal (%edi),%eax - subl %esi,%eax - jo idiff_err -.end - -.inline Xisub32n,0 - leal (%edi),%eax - subl %esi,%eax - jo idiffn_err -.end - .inline plus_err_label,0 plus_err: .end diff --git a/src/dspSPARC.il b/src/dspSPARC.il index fb5e808..b083c2c 100755 --- a/src/dspSPARC.il +++ b/src/dspSPARC.il @@ -131,80 +131,6 @@ done: ! else done; nop .end -/* - *************************************************************** - Arithmetic Opcode Helpers - *************************************************************** -*/ - -.inline _sub32,8 - subcc %o0,%o1,%o0 ! result = arg0 - arg1 - bvs diff_err - nop -.end - -.inline _isub32,8 - subcc %o0,%o1,%o0 ! result = arg0 - arg1 - bvs idiff_err - nop -.end - -.inline _sub32n,8 - subcc %o0,%o1,%o0 ! result = arg0 - arg1 - bvs diff_err2 - nop -.end - -.inline _mpy32,8 - ba mpy_err - nop -.end - -.inline _impy32,8 - ba impy_err - nop -.end - -.inline _quot32,8 - ba quot_err - nop -.end - -.inline _iquot32,8 - ba iquot_err - nop -.end - -.inline _rem32,8 - ba rem_err - nop -.end - -.inline _irem32,8 - ba irem_err - nop -.end - - -.inline _plus32,8 - addcc %o0,%o1,%o0 ! result = arg0 + arg1 - bvs plus_err - nop -.end - -.inline _iplus32,8 - addcc %o0,%o1,%o0 ! result = arg0 + arg1 - bvs iplus_err - nop -.end - -.inline _iplus32n,8 - addcc %o0,%o1,%o0 ! result = arg0 + arg1 - bvs iplusn_err - nop -.end - - /* *************************************************************** Inline Assembly help for dispatcher.