On 8/18/24 11:23 PM, pan2...@intel.com wrote:
From: Pan Li <pan2...@intel.com>
This patch would like to allow IMM for the operand 0 of ussub pattern.
Aka .SAT_SUB(1023, y) as the below example.
Form 1:
#define DEF_SAT_U_SUB_IMM_FMT_1(T, IMM) \
T __attribute__((noinline)) \
sat_u_sub_imm##IMM##_##T##_fmt_1 (T y) \
{ \
return (T)IMM >= y ? (T)IMM - y : 0; \
}
DEF_SAT_U_SUB_IMM_FMT_1(uint64_t, 1023)
Before this patch:
10 │ sat_u_sub_imm82_uint64_t_fmt_1:
11 │ li a5,82
12 │ bgtu a0,a5,.L3
13 │ sub a0,a5,a0
14 │ ret
15 │ .L3:
16 │ li a0,0
17 │ ret
After this patch:
10 │ sat_u_sub_imm82_uint64_t_fmt_1:
11 │ li a5,82
12 │ sltu a4,a5,a0
13 │ addi a4,a4,-1
14 │ sub a0,a5,a0
15 │ and a0,a4,a0
16 │ ret
The below test suites are passed for this patch:
1. The rv64gcv fully regression test.
gcc/ChangeLog:
* config/riscv/riscv.cc (riscv_gen_unsigned_xmode_reg): Add new
func impl to gen xmode rtx reg from operand rtx.
(riscv_expand_ussub): Gen xmode reg for operand 1.
* config/riscv/riscv.md: Allow const_int for operand 1.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/sat_arith.h: Add test helper macro.
* gcc.target/riscv/sat_u_sub_imm-1.c: New test.
* gcc.target/riscv/sat_u_sub_imm-1_1.c: New test.
* gcc.target/riscv/sat_u_sub_imm-1_2.c: New test.
* gcc.target/riscv/sat_u_sub_imm-2.c: New test.
* gcc.target/riscv/sat_u_sub_imm-2_1.c: New test.
* gcc.target/riscv/sat_u_sub_imm-2_2.c: New test.
* gcc.target/riscv/sat_u_sub_imm-3.c: New test.
* gcc.target/riscv/sat_u_sub_imm-3_1.c: New test.
* gcc.target/riscv/sat_u_sub_imm-3_2.c: New test.
* gcc.target/riscv/sat_u_sub_imm-4.c: New test.
* gcc.target/riscv/sat_u_sub_imm-run-1.c: New test.
* gcc.target/riscv/sat_u_sub_imm-run-2.c: New test.
* gcc.target/riscv/sat_u_sub_imm-run-3.c: New test.
* gcc.target/riscv/sat_u_sub_imm-run-4.c: New test.
OK. I'm assuming we don't have to worry about the case where X is wider
than Xmode? ie, a DImode on rv32?
Jeff
