RISC-V: Apply vla vs. vls mode heuristic vector COST model

RISC-V: Apply vla vs. vls mode heuristic vector COST model

This patch apply vla vs. vls mode heuristic which can fixes the following FAILs:
FAIL: gcc.target/riscv/rvv/autovec/pr111751.c -O3 -ftree-vectorize
scan-assembler-not vset
FAIL: gcc.target/riscv/rvv/autovec/pr111751.c -O3 -ftree-vectorize
scan-assembler-times li\\s+[a-x0-9]+,0\\s+ret 2

The root cause of this FAIL is we failed to pick VLS mode for the vectorization.

Before this patch:

foo2:
        addi    sp,sp,-208
        addi    a2,sp,64
        addi    a5,sp,128
        lui     a6,%hi(.LANCHOR0)
        sd      ra,200(sp)
        addi    a6,a6,%lo(.LANCHOR0)
        mv      a0,a2
        mv      a1,a5
        li      a3,16
        mv      a4,sp
        vsetivli        zero,8,e64,m8,ta,ma
        vle64.v v8,0(a6)
        vse64.v v8,0(a2)
        vse64.v v8,0(a5)
.L4:
        vsetvli a5,a3,e32,m1,ta,ma
        slli    a2,a5,2
        vle32.v v2,0(a1)
        vle32.v v1,0(a0)
        sub     a3,a3,a5
        vadd.vv v1,v1,v2
        vse32.v v1,0(a4)
        add     a1,a1,a2
        add     a0,a0,a2
        add     a4,a4,a2
        bne     a3,zero,.L4
        lw      a4,128(sp)
        lw      a5,64(sp)
        addw    a5,a5,a4
        lw      a4,0(sp)
        bne     a4,a5,.L5
        lw      a4,132(sp)
        lw      a5,68(sp)
        addw    a5,a5,a4
        lw      a4,4(sp)
        bne     a4,a5,.L5
        lw      a4,136(sp)
        lw      a5,72(sp)
        addw    a5,a5,a4
        lw      a4,8(sp)
        bne     a4,a5,.L5
        lw      a4,140(sp)
        lw      a5,76(sp)
        addw    a5,a5,a4
        lw      a4,12(sp)
        bne     a4,a5,.L5
        lw      a4,144(sp)
        lw      a5,80(sp)
        addw    a5,a5,a4
        lw      a4,16(sp)
        bne     a4,a5,.L5
        lw      a4,148(sp)
        lw      a5,84(sp)
        addw    a5,a5,a4
        lw      a4,20(sp)
        bne     a4,a5,.L5
        lw      a4,152(sp)
        lw      a5,88(sp)
        addw    a5,a5,a4
        lw      a4,24(sp)
        bne     a4,a5,.L5
        lw      a4,156(sp)
        lw      a5,92(sp)
        addw    a5,a5,a4
        lw      a4,28(sp)
        bne     a4,a5,.L5
        lw      a4,160(sp)
        lw      a5,96(sp)
        addw    a5,a5,a4
        lw      a4,32(sp)
        bne     a4,a5,.L5
        lw      a4,164(sp)
        lw      a5,100(sp)
        addw    a5,a5,a4
        lw      a4,36(sp)
        bne     a4,a5,.L5
        lw      a4,168(sp)
        lw      a5,104(sp)
        addw    a5,a5,a4
        lw      a4,40(sp)
        bne     a4,a5,.L5
        lw      a4,172(sp)
        lw      a5,108(sp)
        addw    a5,a5,a4
        lw      a4,44(sp)
        bne     a4,a5,.L5
        lw      a4,176(sp)
        lw      a5,112(sp)
        addw    a5,a5,a4
        lw      a4,48(sp)
        bne     a4,a5,.L5
        lw      a4,180(sp)
        lw      a5,116(sp)
        addw    a5,a5,a4
        lw      a4,52(sp)
        bne     a4,a5,.L5
        lw      a4,184(sp)
        lw      a5,120(sp)
        addw    a5,a5,a4
        lw      a4,56(sp)
        bne     a4,a5,.L5
        lw      a4,188(sp)
        lw      a5,124(sp)
        addw    a5,a5,a4
        lw      a4,60(sp)
        bne     a4,a5,.L5
        ld      ra,200(sp)
        li      a0,0
        addi    sp,sp,208
        jr      ra
.L5:
        call    abort

After this patch:

        li      a0,0
        ret

The heuristic leverage ARM SVE and fully tested and confirm we have same behavior
as ARM SVE GCC and RVV Clang.

gcc/ChangeLog:

	* config/riscv/riscv-vector-costs.cc (costs::analyze_loop_vinfo): New function.
	(costs::record_potential_vls_unrolling): Ditto.
	(costs::prefer_unrolled_loop): Ditto.
	(costs::better_main_loop_than_p): Ditto.
	(costs::add_stmt_cost): Ditto.
	* config/riscv/riscv-vector-costs.h (enum cost_type_enum): New enum.
	* config/riscv/t-riscv: Add new include files.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/autovec/pr111313.c: Adapt test.
	* gcc.target/riscv/rvv/autovec/vls/shift-3.c: Ditto.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-1.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-10.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-11.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-12.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-2.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-3.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-4.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-5.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-6.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-7.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-8.c: New test.
	* gcc.dg/vect/costmodel/riscv/rvv/vla_vs_vls-9.c: New test.