[PATCH 1/2] MIPS: add pattern insqisi_extended

[PATCH 1/2] MIPS: add pattern insqisi_extended

[YunQiang Su]

This match pattern allows combination (zero_extract:DI 8, 24, QI)
with an sign-extend to 32bit INS instruction on TARGET_64BIT.

The problem is that, for SI mode, if the sign-bit is modified by
bitops, we will need a sign-extend operation.
Since 32bit INS instruction can be sure that result is sign-extended,
and the QImode src register is safe for INS, too.

(insn 19 18 20 2 (set (zero_extract:DI (reg/v:DI 200 [ val ])
            (const_int 8 [0x8])
            (const_int 24 [0x18]))
        (subreg:DI (reg:QI 205) 0)) "../xx.c":7:29 -1
     (nil))
(insn 20 19 23 2 (set (reg/v:DI 200 [ val ])
        (sign_extend:DI (subreg:SI (reg/v:DI 200 [ val ]) 0))) "../xx.c":7:29 -1
     (nil))

Combine try to merge them to:

(insn 20 19 23 2 (set (reg/v:DI 200 [ val ])
        (sign_extend:DI (ior:SI (and:SI (subreg:SI (reg/v:DI 200 [ val ]) 0)
                    (const_int 16777215 [0xffffff]))
                (ashift:SI (subreg:SI (reg:QI 205 [ MEM[(const unsigned char *)buf_8(D) + 3B] ]) 0)
                    (const_int 24 [0x18]))))) "../xx.c":7:29 18 {*insv_extended}
     (expr_list:REG_DEAD (reg:QI 205 [ MEM[(const unsigned char *)buf_8(D) + 3B] ])
        (nil)))

Let's accept this pattern.
Note: with this patch, we cannot get INS yet: rtx_cost treats
that the later one is more expensive than the previous 2.

gcc

	* config/mips/mips.md (insqisi_extended): New pattern.
---
 gcc/config/mips/mips.md | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/gcc/config/mips/mips.md b/gcc/config/mips/mips.md
index 0666310734e..6bc56b0d3da 100644
--- a/gcc/config/mips/mips.md
+++ b/gcc/config/mips/mips.md
@@ -4415,6 +4415,16 @@ (define_insn "*extzv_truncsi_exts"
   [(set_attr "type"     "arith")
    (set_attr "mode"     "SI")])
 
+(define_insn "*insqisi_extended"
+  [(set (match_operand:DI 0 "register_operand" "=d")
+	(sign_extend:DI
+	     (ior:SI (and:SI (subreg:SI (match_dup 0) 0)
+                    (const_int 16777215))
+		    (ashift:SI (subreg:SI (match_operand:QI 1 "register_operand" "d") 0)
+                (const_int 24)))))]
+  "TARGET_64BIT && !TARGET_MIPS16 && ISA_HAS_EXT_INS"
+  "ins\t%0,%1,24,8"
+  [(set_attr "mode" "SI")])
 
 (define_expand "insvmisalign<mode>"
   [(set (zero_extract:GPR (match_operand:BLK 0 "memory_operand")
-- 
2.39.2

[PATCH 2/2] MIPS: define_attr perf_ratio in mips.md

[YunQiang Su]

The accurate cost of an pattern can get with
	 insn_count * perf_ratio

The default value is set to 0 instead of 1, since that
we will need to distinguish the default value and it is
really set for an pattern.  Since it is not set for most
patterns yet, to use it, we will need to be sure that it's
value is greater than 0.

This attr will be used in `mips_insn_cost`.

gcc

	* config/mips/mips.md (perf_ratio): New attribute.
---
 gcc/config/mips/mips.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/gcc/config/mips/mips.md b/gcc/config/mips/mips.md
index 6bc56b0d3da..5abaa7a3a20 100644
--- a/gcc/config/mips/mips.md
+++ b/gcc/config/mips/mips.md
@@ -312,6 +312,10 @@ (define_attr "sync_insn2" "nop,and,xor,not"
 ;; "11" specifies MEMMODEL_ACQUIRE.
 (define_attr "sync_memmodel" "" (const_int 10))
 
+;; Performance ratio.  Add this attr to the slow INSNs.
+;; Used by mips_insn_cost.
+(define_attr "perf_ratio" "" (const_int 0))
+
 ;; Accumulator operand for madd patterns.
 (define_attr "accum_in" "none,0,1,2,3,4,5" (const_string "none"))
 
-- 
2.39.2