sh.c (shift_insns_rtx, [...]): Truncate shift counts to avoid out-of-bounds array accesses.

2009-04-22  Paolo Bonzini  <bonzini@gnu.org>

	* config/sh/sh.c (shift_insns_rtx, shiftcosts, gen_shifty_op,
	sh_dynamicalize_shift_p, shl_and_scr_length): Truncate
	shift counts to avoid out-of-bounds array accesses.

From-SVN: r146553

gcc/ChangeLog

 2009-04-22  Paolo Bonzini  <bonzini@gnu.org>
 
+	* config/sh/sh.c (shift_insns_rtx, shiftcosts, gen_shifty_op,
+	sh_dynamicalize_shift_p, shl_and_scr_length): Truncate
+	shift counts to avoid out-of-bounds array accesses.
+
+2009-04-22  Paolo Bonzini  <bonzini@gnu.org>
+
 	* config/sparc/sparc.h (POINTER_SIZE): Fix comment.
 	(Pmode): Move above.
 

gcc/config/sh/sh.c

@@ -2247,7 +2247,7 @@ int
 shift_insns_rtx (rtx insn)
 {
   rtx set_src = SET_SRC (XVECEXP (PATTERN (insn), 0, 0));
-  int shift_count = INTVAL (XEXP (set_src, 1));
+  int shift_count = INTVAL (XEXP (set_src, 1)) & 31;
   enum rtx_code shift_code = GET_CODE (set_src);
 
   switch (shift_code)
@@ -2286,9 +2286,10 @@ shiftcosts (rtx x)
   if (GET_CODE (XEXP (x, 1)) != CONST_INT)
     return SH_DYNAMIC_SHIFT_COST;
 
-  value = INTVAL (XEXP (x, 1));
+  /* Otherwise, return the true cost in instructions.  Cope with out of range
+     shift counts more or less arbitrarily.  */
+  value = INTVAL (XEXP (x, 1)) & 31;
 
-  /* Otherwise, return the true cost in instructions.  */
   if (GET_CODE (x) == ASHIFTRT)
     {
       int cost = ashiftrt_insns[value];
@@ -2637,7 +2638,7 @@ gen_shifty_op (int code, rtx *operands)
   int max, i;
 
   /* Truncate the shift count in case it is out of bounds.  */
-  value = value & 0x1f;
+  value = value & 31;
 
   if (value == 31)
     {
@@ -2790,7 +2791,7 @@ expand_ashiftrt (rtx *operands)
 int
 sh_dynamicalize_shift_p (rtx count)
 {
-  return shift_insns[INTVAL (count)] > 1 + SH_DYNAMIC_SHIFT_COST;
+  return shift_insns[INTVAL (count) & 31] > 1 + SH_DYNAMIC_SHIFT_COST;
 }
 
 /* Try to find a good way to implement the combiner pattern
@@ -2950,11 +2951,11 @@ int
 shl_and_scr_length (rtx insn)
 {
   rtx set_src = SET_SRC (XVECEXP (PATTERN (insn), 0, 0));
-  int len = shift_insns[INTVAL (XEXP (set_src, 1))];
+  int len = shift_insns[INTVAL (XEXP (set_src, 1)) & 31];
   rtx op = XEXP (set_src, 0);
-  len += shift_insns[INTVAL (XEXP (op, 1))] + 1;
+  len += shift_insns[INTVAL (XEXP (op, 1)) & 31] + 1;
   op = XEXP (XEXP (op, 0), 0);
-  return len + shift_insns[INTVAL (XEXP (op, 1))];
+  return len + shift_insns[INTVAL (XEXP (op, 1)) & 31];
 }
 
 /* Generate rtl for instructions for which shl_and_kind advised a particular