combine.c (UWIDE_SHIFT_LEFT_BY_BITS_PER_WORD): New macro.

* combine.c (UWIDE_SHIFT_LEFT_BY_BITS_PER_WORD): New macro.
(try_combine): Use it.

From-SVN: r39624

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index df04b03..6e2895c 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2001-02-13  Alexandre Oliva  <aoliva@redhat.com>
+
+       * combine.c (UWIDE_SHIFT_LEFT_BY_BITS_PER_WORD): New macro.
+       (try_combine): Use it.
+
 Tue Feb 13 11:37:06 CET 2001  Jan Hubicka  <jh@suse.cz>
 
        * i386.h (SSE_CLASS_P, MMX_CLASS_P, MAYBE_FLOAT_CLASS_P,

diff --git a/gcc/combine.c b/gcc/combine.c
index 662f05f..c2fa5bb 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -146,6 +146,12 @@ static int max_uid_cuid;
 #define INSN_CUID(INSN) \
 (INSN_UID (INSN) > max_uid_cuid ? insn_cuid (INSN) : uid_cuid[INSN_UID (INSN)])
 
+/* In case BITS_PER_WORD == HOST_BITS_PER_WIDE_INT, shifting by
+   BITS_PER_WORD would invoke undefined behavior.  Work around it.  */
+
+#define UWIDE_SHIFT_LEFT_BY_BITS_PER_WORD(val) \
+  (((unsigned HOST_WIDE_INT)(val) << (BITS_PER_WORD - 1)) << 1)
+
 /* Maximum register number, which is the size of the tables below.  */
 
 static unsigned int combine_max_regno;
@@ -1667,7 +1673,7 @@ try_combine (i3, i2, i1, new_direct_jump_p)
          if (HOST_BITS_PER_WIDE_INT < BITS_PER_WORD)
            abort ();
 
-         lo &= ~(((unsigned HOST_WIDE_INT)1 << BITS_PER_WORD) - 1);
+         lo &= ~(UWIDE_SHIFT_LEFT_BY_BITS_PER_WORD (1) - 1);
          lo |= INTVAL (SET_SRC (PATTERN (i3)));
        }
       else if (HOST_BITS_PER_WIDE_INT == BITS_PER_WORD)
@@ -1677,9 +1683,10 @@ try_combine (i3, i2, i1, new_direct_jump_p)
          int sign = -(int) ((unsigned HOST_WIDE_INT) lo
                             >> (HOST_BITS_PER_WIDE_INT - 1));
 
-         lo &= ~((((unsigned HOST_WIDE_INT)1 << BITS_PER_WORD) - 1)
-                 << BITS_PER_WORD);
-         lo |= INTVAL (SET_SRC (PATTERN (i3))) << BITS_PER_WORD;
+         lo &= ~ (UWIDE_SHIFT_LEFT_BY_BITS_PER_WORD
+                  (UWIDE_SHIFT_LEFT_BY_BITS_PER_WORD (1) - 1));
+         lo |= (UWIDE_SHIFT_LEFT_BY_BITS_PER_WORD
+                (INTVAL (SET_SRC (PATTERN (i3)))));
          if (hi == sign)
            hi = lo < 0 ? -1 : 0;
        }