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libtcc1: Fix integer division, modulo and shifting procedures.

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* lib/libtcc1.c (__divdi3): Make parameters integer.
(__moddi3): Make parameters integer.
(__udivdi3): Use unsigned division.
(__umoddi3): Use unsigned modulo.
(__lshrdi3): Add comment.
(__ashrdi3): Add comment.
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Danny Milosavljevic 2021-02-08 19:31:53 +01:00 committed by Jan (janneke) Nieuwenhuizen
parent 27b06c6ddb
commit 2e9b02043b
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GPG key ID: F3C1A0D9C1D65273
1 changed files with 23 additions and 8 deletions
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31
lib/libtcc1.c
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@ -1,6 +1,7 @@
/* -*-comment-start: "//";comment-end:""-*-
* GNU Mes --- Maxwell Equations of Software
* Copyright © 2017,2018,2020 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
* Copyright © 2021 Danny Milosavljevic <dannym@scratchpost.org>
*
* This file is part of GNU Mes.
*
@ -20,8 +21,13 @@
#include <mes/lib.h>
double
__divdi3 (double a, double b)
#if HAVE_LONG_LONG
long long
__divdi3 (long long a, long long b)
#else
long
__divdi3 (long a, long b)
#endif
{
#if !__TINYC__
static int stub = 0;
@ -29,6 +35,7 @@ __divdi3 (double a, double b)
eputs ("__divdi3 stub\n");
stub = 1;
#endif
// FIXME: Actually use long long
long ai = a;
long bi = b;
#if __arm__ && __TINYC__
@ -38,8 +45,13 @@ __divdi3 (double a, double b)
#endif
}
double
__moddi3 (double a, double b)
#if HAVE_LONG_LONG
long long
__moddi3 (long long a, long long b)
#else
long
__moddi3 (long a, long b)
#endif
{
#if !__TINYC__
static int stub = 0;
@ -47,6 +59,7 @@ __moddi3 (double a, double b)
eputs ("__moddi3 stub\n");
stub = 1;
#endif
// FIXME: Actually use long long
long ai = a;
long bi = b;
#if __arm__ && __TINYC__
@ -70,12 +83,13 @@ __udivdi3 (unsigned long a, long ah, unsigned long b)
eputs ("__udivdi3 stub\n");
stub = 1;
#endif
// FIXME: Actually use long long
unsigned long ai = a;
unsigned long bi = b;
if (!b)
return 0;
#if __arm__ && __TINYC__
return __mesabi_idiv (ai, bi);
return __mesabi_udiv (ai, bi);
#else
return ai / bi;
#endif
@ -95,10 +109,11 @@ __umoddi3 (unsigned long a, long ah, unsigned long b)
eputs ("__umoddi3 stub\n");
stub = 1;
#endif
// FIXME: Actually use long long
unsigned long ai = a;
unsigned long bi = b;
#if __arm__ && __TINYC__
return __mesabi_imod (ai, bi);
return __mesabi_umod (ai, bi);
#else
return ai % bi;
#endif
@ -121,7 +136,7 @@ __lshrdi3 (unsigned long a, long ah, long b)
#else // __TINYC__
for (int i = 0; i < b; i++)
#if __arm__
a = __mesabi_idiv (a, 2);
a = __mesabi_udiv (a, 2); // I sure hope that doesn't endless recurse because of the optimizations in __mesabi_udiv that shift
#else // !__arm__
a /= 2;
#endif // !__arm__
@ -167,7 +182,7 @@ __ashrdi3 (long a, long ah, long b)
#else // __TINYC__
for (int i = 0; i < b; i++)
#if __arm__
a = __mesabi_idiv (a, 2);
a = __mesabi_idiv (a, 2); // I sure hope that doesn't endless recurse because of the optimizations in __mesabi_udiv that shift
#else // !__arm__
a /= 2;
#endif // !__arm__