[gcc(refs/users/macro/heads/vax-mode-cc)] VAX: Fix predicates for widening multiply and multiply-add insns

[Maciej W. Rozycki]

https://gcc.gnu.org/g:de54ad8ef0c03ddccfa6119edcd7fb7dc73dd0cb

commit de54ad8ef0c03ddccfa6119edcd7fb7dc73dd0cb
Author: Maciej W. Rozycki <macro@linux-mips.org>
Date:   Fri Nov 20 02:26:55 2020 +0000

    VAX: Fix predicates for widening multiply and multiply-add insns
    
    It makes no sense for insn operand predicates, as long as they accept a
    register operand, to be more restrictive than the set of the associated
    constraints, because expand will choose the insn based on the relevant
    operand being a pseudo register then and reload will keep it happily as
    an immediate if a constraint permits it.  So the restriction posed by
    such a predicate will be happily ignored, and moreover if a splitter is
    added, such as required for MODE_CC support, the new instructions will
    reject the original operands supplied, causing an ICE like below:
    
    .../gcc/testsuite/gfortran.dg/graphite/PR67518.f90:44:0: Error: could not split insn
    (insn 90 662 663 (set (reg:DI 10 %r10 [orig:97 _235 ] [97])
            (mult:DI (sign_extend:DI (mem/c:SI (plus:SI (reg/f:SI 13 %fp)
                            (const_int -800 [0xfffffffffffffce0])) [14 %sfp+-800 S4 A32]))
                (sign_extend:DI (const_int -51 [0xffffffffffffffcd])))) 299 {mulsidi3}
         (expr_list:REG_EQUAL (mult:DI (sign_extend:DI (subreg:SI (mem/c:DI (plus:SI (reg/f:SI 13 %fp)
                                (const_int -800 [0xfffffffffffffce0])) [14 %sfp+-800 S8 A32]) 0))
                (const_int -51 [0xffffffffffffffcd]))
            (nil)))
    during RTL pass: final
    .../gcc/testsuite/gfortran.dg/graphite/PR67518.f90:44:0: internal compiler error: in final_scan_insn_1, at final.c:3073
    Please submit a full bug report,
    with preprocessed source if appropriate.
    See <https://gcc.gnu.org/bugs/> for instructions.
    
    Change the predicates used with the widening multiply and multiply-add
    insns to allow immediates then, just as the constraints and the machine
    instructions produced permit.
    
    Also give the insns names, for easier reference here and elsewhere.
    
            gcc/
            * config/vax/vax.md (mulsidi3): Fix the multiplicand predicates.
            (*maddsidi4, *maddsidi4_const): Likewise.  Name insns.

Diff:
---
 gcc/config/vax/vax.md | 31 ++++++++++++++-----------------
 1 file changed, 14 insertions(+), 17 deletions(-)

diff --git a/gcc/config/vax/vax.md b/gcc/config/vax/vax.md
index 34fdf67bb6d..2f6643abe5c 100644
--- a/gcc/config/vax/vax.md
+++ b/gcc/config/vax/vax.md
@@ -445,35 +445,32 @@
 
 (define_insn "mulsidi3"
   [(set (match_operand:DI 0 "nonimmediate_operand" "=g")
-	(mult:DI (sign_extend:DI
-		  (match_operand:SI 1 "nonimmediate_operand" "nrmT"))
-		 (sign_extend:DI
-		  (match_operand:SI 2 "nonimmediate_operand" "nrmT"))))]
+	(mult:DI
+	  (sign_extend:DI (match_operand:SI 1 "general_operand" "nrmT"))
+	  (sign_extend:DI (match_operand:SI 2 "general_operand" "nrmT"))))]
   ""
   "emul %1,%2,$0,%0")
 
-(define_insn ""
+(define_insn "*maddsidi4"
   [(set (match_operand:DI 0 "nonimmediate_operand" "=g")
 	(plus:DI
-	 (mult:DI (sign_extend:DI
-		   (match_operand:SI 1 "nonimmediate_operand" "nrmT"))
-		  (sign_extend:DI
-		   (match_operand:SI 2 "nonimmediate_operand" "nrmT")))
-	 (sign_extend:DI (match_operand:SI 3 "nonimmediate_operand" "g"))))]
+	  (mult:DI
+	    (sign_extend:DI (match_operand:SI 1 "general_operand" "nrmT"))
+	    (sign_extend:DI (match_operand:SI 2 "general_operand" "nrmT")))
+	  (sign_extend:DI (match_operand:SI 3 "general_operand" "g"))))]
   ""
   "emul %1,%2,%3,%0")
 
 ;; 'F' constraint means type CONST_DOUBLE
-(define_insn ""
+(define_insn "*maddsidi4_const"
   [(set (match_operand:DI 0 "nonimmediate_operand" "=g")
 	(plus:DI
-	 (mult:DI (sign_extend:DI
-		   (match_operand:SI 1 "nonimmediate_operand" "nrmT"))
-		  (sign_extend:DI
-		   (match_operand:SI 2 "nonimmediate_operand" "nrmT")))
-	 (match_operand:DI 3 "immediate_operand" "F")))]
+	  (mult:DI
+	    (sign_extend:DI (match_operand:SI 1 "general_operand" "nrmT"))
+	    (sign_extend:DI (match_operand:SI 2 "general_operand" "nrmT")))
+	  (match_operand:DI 3 "immediate_operand" "F")))]
   "GET_CODE (operands[3]) == CONST_DOUBLE
-    && CONST_DOUBLE_HIGH (operands[3]) == (CONST_DOUBLE_LOW (operands[3]) >> 31)"
+   && CONST_DOUBLE_HIGH (operands[3]) == (CONST_DOUBLE_LOW (operands[3]) >> 31)"
   "*
 {
   if (CONST_DOUBLE_HIGH (operands[3]))