RISC-V: Fix pred_mov constraint for vle.v
authorJu-Zhe Zhong <juzhe.zhong@rivai.ai>
Thu, 19 Jan 2023 07:02:58 +0000 (15:02 +0800)
committerKito Cheng <kito.cheng@sifive.com>
Fri, 27 Jan 2023 10:02:15 +0000 (18:02 +0800)
The original constraint is incorrect in pred_mov pattern.
Take a look at Alternative 2, the operands[0] is "vr",
operands[1] which is mask operand can be "vm".
Such alternative matching will give the wrong codegen (vle.v v0,0(a5),v0.t)
This is illegal according to RVV ISA.

To fix this issue and not destroy the RA performance, fix this pattern in
this patch.

gcc/ChangeLog:

* config/riscv/vector.md: Fix constraints.

gcc/config/riscv/vector.md

index 7d84f9e..1dd81ae 100644 (file)
 ;;    2. (const_vector:VNx1SF repeat [
 ;;                (const_double:SF 0.0 [0x0.0p+0])]).
 (define_insn_and_split "@pred_mov<mode>"
-  [(set (match_operand:V 0 "nonimmediate_operand"          "=vd,    vr,     m,    vr,    vr")
-       (if_then_else:V
-         (unspec:<VM>
-           [(match_operand:<VM> 1 "vector_mask_operand" "vmWc1, vmWc1, vmWc1,   Wc1,   Wc1")
-            (match_operand 4 "vector_length_operand"    "   rK,    rK,    rK,    rK,    rK")
-            (match_operand 5 "const_int_operand"        "    i,     i,     i,     i,     i")
-            (match_operand 6 "const_int_operand"        "    i,     i,     i,     i,     i")
-            (match_operand 7 "const_int_operand"        "    i,     i,     i,     i,     i")
-            (reg:SI VL_REGNUM)
-            (reg:SI VTYPE_REGNUM)] UNSPEC_VPREDICATE)
-         (match_operand:V 3 "vector_move_operand"       "    m,     m,    vr,    vr, viWc0")
-         (match_operand:V 2 "vector_merge_operand"      "    0,    vu,    vu,   vu0,   vu0")))]
+  [(set (match_operand:V 0 "nonimmediate_operand"      "=vr,    vr,    vd,     m,    vr,    vr")
+    (if_then_else:V
+      (unspec:<VM>
+        [(match_operand:<VM> 1 "vector_mask_operand" "vmWc1,   Wc1,    vm, vmWc1,   Wc1,   Wc1")
+         (match_operand 4 "vector_length_operand"    "   rK,    rK,    rK,    rK,    rK,    rK")
+         (match_operand 5 "const_int_operand"        "    i,     i,     i,     i,     i,     i")
+         (match_operand 6 "const_int_operand"        "    i,     i,     i,     i,     i,     i")
+         (match_operand 7 "const_int_operand"        "    i,     i,     i,     i,     i,     i")
+         (reg:SI VL_REGNUM)
+         (reg:SI VTYPE_REGNUM)] UNSPEC_VPREDICATE)
+      (match_operand:V 3 "vector_move_operand"       "    m,     m,     m,    vr,    vr, viWc0")
+      (match_operand:V 2 "vector_merge_operand"      "    0,    vu,    vu,    vu,   vu0,   vu0")))]
   "TARGET_VECTOR"
   "@
    vle<sew>.v\t%0,%3%p1
-   vle<sew>.v\t%0,%3%p1
+   vle<sew>.v\t%0,%3
+   vle<sew>.v\t%0,%3,%1.t
    vse<sew>.v\t%3,%0%p1
    vmv.v.v\t%0,%3
    vmv.v.i\t%0,%v3"
    && satisfies_constraint_vu (operands[2])"
   [(set (match_dup 0) (match_dup 3))]
   ""
-  [(set_attr "type" "vlde,vlde,vste,vimov,vimov")
+  [(set_attr "type" "vlde,vlde,vlde,vste,vimov,vimov")
    (set_attr "mode" "<MODE>")])
 
 ;; Dedicated pattern for vse.v instruction since we can't reuse pred_mov pattern to include