combine.c (try_combine): Do simplification only call of subst() on i2 even when i1...

2011-03-18  Chung-Lin Tang  <cltang@codesourcery.com>

	* combine.c (try_combine): Do simplification only call of
	subst() on i2 even when i1 is present. Update comments.

	testsuite/
	* gcc.target/arm/unsigned-extend-1.c: New.

From-SVN: r171138

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8c4233df2b55098809bf04ddaec34e34bd8bcdc7..176a13a539938fce4de23cbd00fb1bdbf0692e14 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2011-03-18  Chung-Lin Tang  <cltang@codesourcery.com>
+
+       * combine.c (try_combine): Do simplification only call of
+       subst() on i2 even when i1 is present. Update comments.
+
 2011-03-18  Kaz Kojima  <kkojima@gcc.gnu.org>
 
        * config/sh/sh.c (sh_delegitimize_address): Handle UNSPEC_SYMOFF

diff --git a/gcc/combine.c b/gcc/combine.c
index f9d33b3d539120c6a76c0d24b85e1e36ca9ba5f0..fe3302a492d733ef05e86f2469ca87534578746d 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -3063,7 +3063,7 @@ try_combine (rtx i3, rtx i2, rtx i1, rtx i0, int *new_direct_jump_p)
       /* It is possible that the source of I2 or I1 may be performing
         an unneeded operation, such as a ZERO_EXTEND of something
         that is known to have the high part zero.  Handle that case
-        by letting subst look at the innermost one of them.
+        by letting subst look at the inner insns.
 
         Another way to do this would be to have a function that tries
         to simplify a single insn instead of merging two or more
@@ -3088,11 +3088,9 @@ try_combine (rtx i3, rtx i2, rtx i1, rtx i0, int *new_direct_jump_p)
              subst_low_luid = DF_INSN_LUID (i1);
              i1src = subst (i1src, pc_rtx, pc_rtx, 0, 0);
            }
-         else
-           {
-             subst_low_luid = DF_INSN_LUID (i2);
-             i2src = subst (i2src, pc_rtx, pc_rtx, 0, 0);
-           }
+
+         subst_low_luid = DF_INSN_LUID (i2);
+         i2src = subst (i2src, pc_rtx, pc_rtx, 0, 0);
        }
 
       n_occurrences = 0;               /* `subst' counts here */

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 59d736a71f8bd8e572b4788863ef5aedaf187114..5897ac34255af48fb80cd63ba4b8f29a5f715d79 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2011-03-18  Chung-Lin Tang  <cltang@codesourcery.com>
+
+       * gcc.target/arm/unsigned-extend-1.c: New.
+
 2011-03-18  Jakub Jelinek  <jakub@redhat.com>
 
        PR bootstrap/48161

diff --git a/gcc/testsuite/gcc.target/arm/unsigned-extend-1.c b/gcc/testsuite/gcc.target/arm/unsigned-extend-1.c
new file mode 100644 (file)
index 0000000..6c55561
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/unsigned-extend-1.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=armv6" } */
+
+unsigned char foo (unsigned char c)
+{
+  return (c >= '0') && (c <= '9');
+}
+
+/* { dg-final { scan-assembler-not "uxtb" } } */