summaryrefslogtreecommitdiff
path: root/recipes/gcc/gcc-csl-arm/gcc_optab_arm.patch
diff options
context:
space:
mode:
Diffstat (limited to 'recipes/gcc/gcc-csl-arm/gcc_optab_arm.patch')
-rw-r--r--recipes/gcc/gcc-csl-arm/gcc_optab_arm.patch95
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);
++}