diff options
Diffstat (limited to 'recipes/gcc/gcc-csl-arm/gcc_optab_arm.patch')
| -rw-r--r-- | recipes/gcc/gcc-csl-arm/gcc_optab_arm.patch | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/recipes/gcc/gcc-csl-arm/gcc_optab_arm.patch b/recipes/gcc/gcc-csl-arm/gcc_optab_arm.patch new file mode 100644 index 0000000000..fa21b26554 --- /dev/null +++ b/recipes/gcc/gcc-csl-arm/gcc_optab_arm.patch @@ -0,0 +1,95 @@ +ARM is the only architecture that has a helper function that returns +an unbiased result. This fix is trivial enough that we can show it +doesn't effect any of the other arches. Can we consider this a +regression fix since it used to work until the helper was added :} + +Tested with no regressions on x86_64-pc-linux-gnu and arm-none-eabi. + +Cheers, +Carlos. +-- +Carlos O'Donell +CodeSourcery +carlos@codesourcery.com +(650) 331-3385 x716 + +gcc/ + +2006-01-27 Carlos O'Donell <carlos@codesourcery.com> + + * optabs.c (prepare_cmp_insn): If unbaised and unsigned then bias + the comparison routine return. + +gcc/testsuite/ + +2006-01-27 Carlos O'Donell <carlos@codesourcery.com> + + * gcc.dg/unsigned-long-compare.c: New test. + +Index: gcc/optabs.c +=================================================================== +--- 1/gcc/optabs.c (revision 110300) ++++ 2/gcc/optabs.c (working copy) +@@ -3711,18 +3711,24 @@ + result = emit_library_call_value (libfunc, NULL_RTX, LCT_CONST_MAKE_BLOCK, + word_mode, 2, x, mode, y, mode); + ++ /* There are two kinds of comparison routines. Biased routines ++ return 0/1/2, and unbiased routines return -1/0/1. Other parts ++ of gcc expect that the comparison operation is equivalent ++ to the modified comparison. For signed comparisons compare the ++ result against 1 in the unbiased case, and zero in the biased ++ case. For unsigned comparisons always compare against 1 after ++ biasing the unbased result by adding 1. This gives us a way to ++ represent LTU. */ + *px = result; + *pmode = word_mode; +- if (TARGET_LIB_INT_CMP_BIASED) +- /* Integer comparison returns a result that must be compared +- against 1, so that even if we do an unsigned compare +- afterward, there is still a value that can represent the +- result "less than". */ +- *py = const1_rtx; +- else ++ *py = const1_rtx; ++ ++ if (!TARGET_LIB_INT_CMP_BIASED) + { +- *py = const0_rtx; +- *punsignedp = 1; ++ if (*punsignedp) ++ *px = plus_constant (result, 1); ++ else ++ *py = const0_rtx; + } + return; + } +Index: gcc/testsuite/gcc.dg/unsigned-long-compare.c +=================================================================== +--- 1/gcc/testsuite/gcc.dg/unsigned-long-compare.c (revision 0) ++++ 2/gcc/testsuite/gcc.dg/unsigned-long-compare.c (revision 0) +@@ -0,0 +1,24 @@ ++/* Copyright (C) 2006 Free Software Foundation, Inc. */ ++/* Contributed by Carlos O'Donell on 2006-01-27 */ ++ ++/* Test a division corner case where the expression simplifies ++ to a comparison, and the optab expansion is wrong. The optab ++ expansion emits a function whose return is unbiased and needs ++ adjustment. */ ++/* Origin: Carlos O'Donell <carlos@codesourcery.com> */ ++/* { dg-do run { target arm-*-*eabi* } } */ ++/* { dg-options "" } */ ++#include <stdlib.h> ++ ++#define BIG_CONSTANT 0xFFFFFFFF80000000ULL ++ ++int main (void) ++{ ++ unsigned long long OneULL = 1ULL; ++ unsigned long long result; ++ ++ result = OneULL / BIG_CONSTANT; ++ if (result) ++ abort (); ++ exit (0); ++} |