expmed.c (extract_bit_field): Reverse operands of && condition to prevent a potential...

	* expmed.c (extract_bit_field): Reverse operands of && condition to
        prevent a potential division by zero in the previously first branch.
	* config/pa/pa.md (extv, extzv): FAIL if the bitfield length is zero.

From-SVN: r65907

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index decc4b1..ec107c8 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -3,6 +3,10 @@
        * calls.c (expand_call): Prevent sibcall optimization for calls to
        nested subprograms.
 
+       * expmed.c (extract_bit_field): Reverse operands of && condition to
+        prevent a potential division by zero in the previously first branch.
+       * config/pa/pa.md (extv, extzv): FAIL if the bitfield length is zero.
+
 2003-04-21  Joel Brobecker  <brobecker@gnat.com>
 
        * dwarf2out.c (is_ada, is_ada_subrange_type): New functions.

diff --git a/gcc/config/pa/pa.md b/gcc/config/pa/pa.md
index 523b971..1d69c20 100644 (file)
--- a/gcc/config/pa/pa.md
+++ b/gcc/config/pa/pa.md
@@ -7153,6 +7153,10 @@
   ""
   "
 {
+  /* PA extraction insns don't support zero length bitfields.  */
+  if (INTVAL (operands[2]) == 0)
+    FAIL;
+
   if (TARGET_64BIT)
     emit_insn (gen_extzv_64 (operands[0], operands[1],
                             operands[2], operands[3]));
@@ -7215,6 +7219,10 @@
   ""
   "
 {
+  /* PA extraction insns don't support zero length bitfields.  */
+  if (INTVAL (operands[2]) == 0)
+    FAIL;
+
   if (TARGET_64BIT)
     emit_insn (gen_extv_64 (operands[0], operands[1],
                            operands[2], operands[3]));

diff --git a/gcc/expmed.c b/gcc/expmed.c
index b48576b..5cc0894 100644 (file)
--- a/gcc/expmed.c
+++ b/gcc/expmed.c
@@ -1104,25 +1104,25 @@ extract_bit_field (str_rtx, bitsize, bitnum, unsignedp,
            ? mode
            : mode_for_size (bitsize, GET_MODE_CLASS (tmode), 0));
 
-  if (((GET_CODE (op0) != MEM
-       && TRULY_NOOP_TRUNCATION (GET_MODE_BITSIZE (mode),
-                                 GET_MODE_BITSIZE (GET_MODE (op0)))
-       && GET_MODE_SIZE (mode1) != 0
-       && byte_offset % GET_MODE_SIZE (mode1) == 0)
-       || (GET_CODE (op0) == MEM
-          && (! SLOW_UNALIGNED_ACCESS (mode, MEM_ALIGN (op0))
-              || (offset * BITS_PER_UNIT % bitsize == 0
-                  && MEM_ALIGN (op0) % bitsize == 0))))
-      && ((bitsize >= BITS_PER_WORD && bitsize == GET_MODE_BITSIZE (mode)
-          && bitpos % BITS_PER_WORD == 0)
-         || (mode_for_size (bitsize, GET_MODE_CLASS (tmode), 0) != BLKmode
-             /* ??? The big endian test here is wrong.  This is correct
-                if the value is in a register, and if mode_for_size is not
-                the same mode as op0.  This causes us to get unnecessarily
-                inefficient code from the Thumb port when -mbig-endian.  */
-             && (BYTES_BIG_ENDIAN
-                 ? bitpos + bitsize == BITS_PER_WORD
-                 : bitpos == 0))))
+  if (((bitsize >= BITS_PER_WORD && bitsize == GET_MODE_BITSIZE (mode)
+       && bitpos % BITS_PER_WORD == 0)
+       || (mode_for_size (bitsize, GET_MODE_CLASS (tmode), 0) != BLKmode
+          /* ??? The big endian test here is wrong.  This is correct
+             if the value is in a register, and if mode_for_size is not
+             the same mode as op0.  This causes us to get unnecessarily
+             inefficient code from the Thumb port when -mbig-endian.  */
+          && (BYTES_BIG_ENDIAN
+              ? bitpos + bitsize == BITS_PER_WORD
+              : bitpos == 0)))
+      && ((GET_CODE (op0) != MEM
+          && TRULY_NOOP_TRUNCATION (GET_MODE_BITSIZE (mode),
+                                    GET_MODE_BITSIZE (GET_MODE (op0)))
+          && GET_MODE_SIZE (mode1) != 0
+          && byte_offset % GET_MODE_SIZE (mode1) == 0)
+         || (GET_CODE (op0) == MEM
+             && (! SLOW_UNALIGNED_ACCESS (mode, MEM_ALIGN (op0))
+                 || (offset * BITS_PER_UNIT % bitsize == 0
+                     && MEM_ALIGN (op0) % bitsize == 0)))))
     {
       if (mode1 != GET_MODE (op0))
        {