(divhisi3, udivhisi3, modhisi3, umodhi3): Comment out.

(divhisi3, udivhisi3, modhisi3, umodhi3 recognizers): Comment out.

From-SVN: r5963

1 files changed, 131 insertions, 124 deletions

diff --git a/gcc/config/m68k/m68k.md b/gcc/config/m68k/m68k.md
index 1de4c57..910c02e 100644
--- a/gcc/config/m68k/m68k.md
+++ b/gcc/config/m68k/m68k.md
@@ -2715,35 +2715,39 @@
 #endif
 }")
 
-(define_insn "divhisi3"
-  [(set (match_operand:HI 0 "general_operand" "=d")
-	(truncate:HI
-	 (div:SI
-	  (match_operand:SI 1 "general_operand" "0")
-	  (sign_extend:SI (match_operand:HI 2 "nonimmediate_operand" "dm")))))]
-  ""
-  "*
-{
-#ifdef MOTOROLA
-  return \"divs%.w %2,%0\";
-#else
-  return \"divs %2,%0\";
-#endif
-}")
-
-(define_insn ""
-  [(set (match_operand:HI 0 "general_operand" "=d")
-	(truncate:HI (div:SI (match_operand:SI 1 "general_operand" "0")
-			     (match_operand:SI 2 "const_int_operand" "n"))))]
-  ""
-  "*
-{
-#ifdef MOTOROLA
-  return \"divs%.w %2,%0\";
-#else
-  return \"divs %2,%0\";
-#endif
-}")
+;; These patterns don't work because the divs instruction is undefined if
+;; the quotient is more than 16 bits.  This valid C would be miscompiled:
+;; int n; short d; unsigned short q; ... q = (unsigned int) (n / d);
+;; Imagine what happens when n = 100000 and d = 1.
+;;(define_insn "divhisi3"
+;;  [(set (match_operand:HI 0 "general_operand" "=d")
+;;	(truncate:HI
+;;	 (div:SI
+;;	  (match_operand:SI 1 "general_operand" "0")
+;;	  (sign_extend:SI (match_operand:HI 2 "nonimmediate_operand" "dm")))))]
+;;  ""
+;;  "*
+;;{
+;;#ifdef MOTOROLA
+;;  return \"divs%.w %2,%0\";
+;;#else
+;;  return \"divs %2,%0\";
+;;#endif
+;;}")
+
+;;(define_insn ""
+;;  [(set (match_operand:HI 0 "general_operand" "=d")
+;;	(truncate:HI (div:SI (match_operand:SI 1 "general_operand" "0")
+;;			     (match_operand:SI 2 "const_int_operand" "n"))))]
+;;  ""
+;;  "*
+;;{
+;;#ifdef MOTOROLA
+;;  return \"divs%.w %2,%0\";
+;;#else
+;;  return \"divs %2,%0\";
+;;#endif
+;;}")
 
 (define_insn "udivhi3"
   [(set (match_operand:HI 0 "general_operand" "=d")
@@ -2759,35 +2763,36 @@
 #endif
 }")
 
-(define_insn "udivhisi3"
-  [(set (match_operand:HI 0 "general_operand" "=d")
-	(truncate:HI
-	 (udiv:SI
-	  (match_operand:SI 1 "general_operand" "0")
-	  (zero_extend:SI (match_operand:HI 2 "nonimmediate_operand" "dm")))))]
-  ""
-  "*
-{
-#ifdef MOTOROLA
-  return \"divu%.w %2,%0\";
-#else
-  return \"divu %2,%0\";
-#endif
-}")
-
-(define_insn ""
-  [(set (match_operand:HI 0 "general_operand" "=d")
-	(truncate:HI (udiv:SI (match_operand:SI 1 "general_operand" "0")
-			      (match_operand:SI 2 "const_int_operand" "n"))))]
-  ""
-  "*
-{
-#ifdef MOTOROLA
-  return \"divu%.w %2,%0\";
-#else
-  return \"divu %2,%0\";
-#endif
-}")
+;; See comment before divhisi3 why these are commented out.
+;;(define_insn "udivhisi3"
+;;  [(set (match_operand:HI 0 "general_operand" "=d")
+;;	(truncate:HI
+;;	 (udiv:SI
+;;	  (match_operand:SI 1 "general_operand" "0")
+;;	  (zero_extend:SI (match_operand:HI 2 "nonimmediate_operand" "dm")))))]
+;;  ""
+;;  "*
+;;{
+;;#ifdef MOTOROLA
+;;  return \"divu%.w %2,%0\";
+;;#else
+;;  return \"divu %2,%0\";
+;;#endif
+;;}")
+
+;;(define_insn ""
+;;  [(set (match_operand:HI 0 "general_operand" "=d")
+;;	(truncate:HI (udiv:SI (match_operand:SI 1 "general_operand" "0")
+;;			      (match_operand:SI 2 "const_int_operand" "n"))))]
+;;  ""
+;;  "*
+;;{
+;;#ifdef MOTOROLA
+;;  return \"divu%.w %2,%0\";
+;;#else
+;;  return \"divu %2,%0\";
+;;#endif
+;;}")
 
 (define_expand "divdf3"
   [(set (match_operand:DF 0 "general_operand" "")
@@ -2888,39 +2893,40 @@
 #endif
 }")
 
-(define_insn "modhisi3"
-  [(set (match_operand:HI 0 "general_operand" "=d")
-	(truncate:HI
-	 (mod:SI
-	  (match_operand:SI 1 "general_operand" "0")
-	  (sign_extend:SI (match_operand:HI 2 "nonimmediate_operand" "dm")))))]
-  ""
-  "*
-{
-  /* The swap insn produces cc's that don't correspond to the result.  */
-  CC_STATUS_INIT;
-#ifdef MOTOROLA
-  return \"divs%.w %2,%0\;swap %0\";
-#else
-  return \"divs %2,%0\;swap %0\";
-#endif
-}")
-
-(define_insn ""
-  [(set (match_operand:HI 0 "general_operand" "=d")
-	(truncate:HI (mod:SI (match_operand:SI 1 "general_operand" "0")
-			     (match_operand:SI 2 "const_int_operand" "n"))))]
-  ""
-  "*
-{
-  /* The swap insn produces cc's that don't correspond to the result.  */
-  CC_STATUS_INIT;
-#ifdef MOTOROLA
-  return \"divs%.w %2,%0\;swap %0\";
-#else
-  return \"divs %2,%0\;swap %0\";
-#endif
-}")
+;; See comment before divhisi3 why these are commented out.
+;;(define_insn "modhisi3"
+;;  [(set (match_operand:HI 0 "general_operand" "=d")
+;;	(truncate:HI
+;;	 (mod:SI
+;;	  (match_operand:SI 1 "general_operand" "0")
+;;	  (sign_extend:SI (match_operand:HI 2 "nonimmediate_operand" "dm")))))]
+;;  ""
+;;  "*
+;;{
+;;  /* The swap insn produces cc's that don't correspond to the result.  */
+;;  CC_STATUS_INIT;
+;;#ifdef MOTOROLA
+;;  return \"divs%.w %2,%0\;swap %0\";
+;;#else
+;;  return \"divs %2,%0\;swap %0\";
+;;#endif
+;;}")
+
+;;(define_insn ""
+;;  [(set (match_operand:HI 0 "general_operand" "=d")
+;;	(truncate:HI (mod:SI (match_operand:SI 1 "general_operand" "0")
+;;			     (match_operand:SI 2 "const_int_operand" "n"))))]
+;;  ""
+;;  "*
+;;{
+;;  /* The swap insn produces cc's that don't correspond to the result.  */
+;;  CC_STATUS_INIT;
+;;#ifdef MOTOROLA
+;;  return \"divs%.w %2,%0\;swap %0\";
+;;#else
+;;  return \"divs %2,%0\;swap %0\";
+;;#endif
+;;}")
 
 (define_insn "umodhi3"
   [(set (match_operand:HI 0 "general_operand" "=d")
@@ -2938,39 +2944,40 @@
 #endif
 }")
 
-(define_insn "umodhisi3"
-  [(set (match_operand:HI 0 "general_operand" "=d")
-	(truncate:HI
-	 (umod:SI
-	  (match_operand:SI 1 "general_operand" "0")
-	  (zero_extend:SI (match_operand:HI 2 "nonimmediate_operand" "dm")))))]
-  ""
-  "*
-{
-  /* The swap insn produces cc's that don't correspond to the result.  */
-  CC_STATUS_INIT;
-#ifdef MOTOROLA
-  return \"divu%.w %2,%0\;swap %0\";
-#else
-  return \"divu %2,%0\;swap %0\";
-#endif
-}")
-
-(define_insn ""
-  [(set (match_operand:HI 0 "general_operand" "=d")
-	(truncate:HI (umod:SI (match_operand:SI 1 "general_operand" "0")
-			      (match_operand:SI 2 "const_int_operand" "n"))))]
-  ""
-  "*
-{
-  /* The swap insn produces cc's that don't correspond to the result.  */
-  CC_STATUS_INIT;
-#ifdef MOTOROLA
-  return \"divu%.w %2,%0\;swap %0\";
-#else
-  return \"divu %2,%0\;swap %0\";
-#endif
-}")
+;; See comment before divhisi3 why these are commented out.
+;;(define_insn "umodhisi3"
+;;  [(set (match_operand:HI 0 "general_operand" "=d")
+;;	(truncate:HI
+;;	 (umod:SI
+;;	  (match_operand:SI 1 "general_operand" "0")
+;;	  (zero_extend:SI (match_operand:HI 2 "nonimmediate_operand" "dm")))))]
+;;  ""
+;;  "*
+;;{
+;;  /* The swap insn produces cc's that don't correspond to the result.  */
+;;  CC_STATUS_INIT;
+;;#ifdef MOTOROLA
+;;  return \"divu%.w %2,%0\;swap %0\";
+;;#else
+;;  return \"divu %2,%0\;swap %0\";
+;;#endif
+;;}")
+
+;;(define_insn ""
+;;  [(set (match_operand:HI 0 "general_operand" "=d")
+;;	(truncate:HI (umod:SI (match_operand:SI 1 "general_operand" "0")
+;;			      (match_operand:SI 2 "const_int_operand" "n"))))]
+;;  ""
+;;  "*
+;;{
+;;  /* The swap insn produces cc's that don't correspond to the result.  */
+;;  CC_STATUS_INIT;
+;;#ifdef MOTOROLA
+;;  return \"divu%.w %2,%0\;swap %0\";
+;;#else
+;;  return \"divu %2,%0\;swap %0\";
+;;#endif
+;;}")
 
 (define_insn "divmodsi4"
   [(set (match_operand:SI 0 "general_operand" "=d")