From a8e1551bdb372aa3cfe754429b5efd6229ae5fdb Mon Sep 17 00:00:00 2001 From: Pan Li Date: Wed, 26 Apr 2023 20:00:06 +0800 Subject: [PATCH] RISC-V: Legitimise the const0_rtx for RVV load/store address This patch try to legitimise the const0_rtx (aka zero register) as the base register for the RVV load/store instructions. For example: vint32m1_t test_vle32_v_i32m1_shortcut (size_t vl) { return __riscv_vle32_v_i32m1 ((int32_t *)0, vl); } Before this patch: li a5,0 vsetvli zero,a1,e32,m1,ta,ma vle32.v v24,0(a5) <- can propagate the const 0 to a5 here vs1r.v v24,0(a0) After this patch: vsetvli zero,a1,e32,m1,ta,ma vle32.v v24,0(zero) vs1r.v v24,0(a0) As above, this patch allow you to propagate the const 0 (aka zero register) to the base register of the RVV Unit-Stride load in the combine pass. This may benefit the underlying RVV auto-vectorization. However, the indexed load failed to perform the optimization and it will be take care of in another PATCH. gcc/ChangeLog: * config/riscv/riscv.cc (riscv_classify_address): Allow const0_rtx for the RVV load/store. gcc/testsuite/ChangeLog: * gcc.target/riscv/rvv/base/zero_base_load_store_optimization.c: New test. Signed-off-by: Pan Li Co-authored-by: Ju-Zhe Zhong --- gcc/config/riscv/riscv.cc | 17 ++- .../base/zero_base_load_store_optimization.c | 134 ++++++++++++++++++ 2 files changed, 149 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/base/zero_base_load_store_optimization.c diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc index ac8e4420896..a2d2dd0bb67 100644 --- a/gcc/config/riscv/riscv.cc +++ b/gcc/config/riscv/riscv.cc @@ -1088,9 +1088,22 @@ riscv_classify_address (struct riscv_address_info *info, rtx x, && riscv_valid_lo_sum_p (info->symbol_type, mode, info->offset)); case CONST_INT: - /* RVV load/store disallow CONST_INT. */ + /* We only allow the const0_rtx for the RVV load/store. For example: + +----------------------------------------------------------+ + | li a5,0 | + | vsetvli zero,a1,e32,m1,ta,ma | + | vle32.v v24,0(a5) <- propagate the const 0 to a5 here. | + | vs1r.v v24,0(a0) | + +----------------------------------------------------------+ + It can be folded to: + +----------------------------------------------------------+ + | vsetvli zero,a1,e32,m1,ta,ma | + | vle32.v v24,0(zero) | + | vs1r.v v24,0(a0) | + +----------------------------------------------------------+ + This behavior will benefit the underlying RVV auto vectorization. */ if (riscv_v_ext_vector_mode_p (mode)) - return false; + return x == const0_rtx; /* Small-integer addresses don't occur very often, but they are legitimate if x0 is a valid base register. */ diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/zero_base_load_store_optimization.c b/gcc/testsuite/gcc.target/riscv/rvv/base/zero_base_load_store_optimization.c new file mode 100644 index 00000000000..9f323b0ba9c --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/rvv/base/zero_base_load_store_optimization.c @@ -0,0 +1,134 @@ +/* { dg-do compile } */ +/* { dg-options "-march=rv64gcv -mabi=lp64 -O3" } */ + +#include "riscv_vector.h" + +#define float32_t float + +// Unit-Stride Load/Store +vint32m1_t test_vle32_v_i32m1_shortcut (size_t vl) +{ + return __riscv_vle32_v_i32m1 ((int32_t *)0, vl); +} + +vuint32m1_t test_vle32_v_u32m1_shortcut (size_t vl) +{ + return __riscv_vle32_v_u32m1 ((int32_t *)0, vl); +} + +vfloat32m1_t test_vle32_v_f32m1_shortcut (size_t vl) +{ + return __riscv_vle32_v_f32m1 ((float32_t *)0, vl); +} + +void test_vse32_v_i32m1_shortcut (vint32m1_t val, size_t vl) +{ + __riscv_vse32_v_i32m1 ((int32_t *)0, val, vl); +} + +void test_vse32_v_u32m1_shortcut (vuint32m1_t val, size_t vl) +{ + __riscv_vse32_v_u32m1 ((uint32_t *)0, val, vl); +} + +void test_vse32_v_f32m1_shortcut (vfloat32m1_t val, size_t vl) +{ + __riscv_vse32_v_f32m1 ((float32_t *)0, val, vl); +} + +// Stride Load/Store +vint32m1_t test_vlse32_v_i32m1_shortcut (ptrdiff_t bstride, size_t vl) +{ + return __riscv_vlse32_v_i32m1 ((int32_t *)0, bstride, vl); +} + +vuint32m1_t test_vlse32_v_u32m1_shortcut (ptrdiff_t bstride, size_t vl) +{ + return __riscv_vlse32_v_u32m1 ((uint32_t *)0, bstride, vl); +} + +vfloat32m1_t test_vlse32_v_f32m1_shortcut (ptrdiff_t bstride, size_t vl) +{ + return __riscv_vlse32_v_f32m1 ((float32_t *)0, bstride, vl); +} + +void test_vsse32_v_i32m1_shortcut (ptrdiff_t bstride, vint32m1_t val, size_t vl) +{ + __riscv_vsse32_v_i32m1 ((int32_t *)0, bstride, val, vl); +} + +void test_vsse32_v_u32m1_shortcut (ptrdiff_t bstride, vuint32m1_t val, size_t vl) +{ + __riscv_vsse32_v_u32m1 ((uint32_t *)0, bstride, val, vl); +} + +void test_vsse32_v_f32m1_shortcut (ptrdiff_t bstride, vfloat32m1_t val,size_t vl) +{ + __riscv_vsse32_v_f32m1 ((float32_t *)0, bstride, val, vl); +} + +// Indexed-Unordered Load/Store +vint32m1_t test_vluxei32_v_i32m1_shortcut (vuint32m1_t bindex, size_t vl) +{ + return __riscv_vluxei32_v_i32m1 ((int32_t *)0, bindex, vl); +} + +vuint32m1_t test_vluxei32_v_u32m1_shortcut (vuint32m1_t bindex, size_t vl) +{ + return __riscv_vluxei32_v_u32m1 ((uint32_t *)0, bindex, vl); +} + +vfloat32m1_t test_vluxei32_v_f32m1_shortcut (vuint32m1_t bindex, size_t vl) +{ + return __riscv_vluxei32_v_f32m1 ((float32_t *)0, bindex, vl); +} + +void test_vsuxei32_v_i32m1_shortcut (vuint32m1_t bindex, vint32m1_t val, size_t vl) +{ + __riscv_vsuxei32_v_i32m1 ((int32_t *)0, bindex, val, vl); +} + +void test_vsuxei32_v_u32m1_shortcut (vuint32m1_t bindex, vuint32m1_t val, size_t vl) +{ + __riscv_vsuxei32_v_u32m1 ((uint32_t *)0, bindex, val, vl); +} + +void test_vsuxei32_v_f32m1_shortcut (vuint32m1_t bindex, vfloat32m1_t val, size_t vl) +{ + __riscv_vsuxei32_v_f32m1 ((float32_t *)0, bindex, val, vl); +} + +// Indexed-Ordered Load/Store +vint32m1_t test_vloxei32_v_i32m1_shortcut (vuint32m1_t bindex, size_t vl) +{ + return __riscv_vloxei32_v_i32m1 ((int32_t *)0, bindex, vl); +} + +vuint32m1_t test_vloxei32_v_u32m1_shortcut (vuint32m1_t bindex, size_t vl) +{ + return __riscv_vloxei32_v_u32m1 ((uint32_t *)0, bindex, vl); +} + +vfloat32m1_t test_vloxei32_v_f32m1_shortcut (vuint32m1_t bindex, size_t vl) +{ + return __riscv_vloxei32_v_f32m1 ((float32_t *)0, bindex, vl); +} + +void test_vsoxei32_v_i32m1_shortcut (vuint32m1_t bindex, vint32m1_t val, size_t vl) +{ + __riscv_vsoxei32_v_i32m1 ((int32_t *)0, bindex, val, vl); +} + +void test_vsoxei32_v_u32m1_shortcut (vuint32m1_t bindex, vuint32m1_t val, size_t vl) +{ + __riscv_vsoxei32_v_u32m1 ((uint32_t *)0, bindex, val, vl); +} + +void test_vsoxei32_v_f32m1_shortcut (vuint32m1_t bindex, vfloat32m1_t val, size_t vl) +{ + __riscv_vsoxei32_v_f32m1 ((float32_t *)0, bindex, val, vl); +} + +/* { dg-final { scan-assembler-times {v[ls]e[0-9]+\.v\s+v[0-9]+,\s*0\(zero\)} 6 } } */ +/* { dg-final { scan-assembler-times {v[ls]se[0-9]+\.v\s+v[0-9]+,\s*0\(zero\),\s*[ax][0-9]+} 6 } } */ +/* { dg-final { scan-assembler-times {li\s+[a-x][0-9]+,\s*0} 12 } } */