When fixing bugs, I notice there is a piece odd codes look incorrect. which probably make codegen worse.
#include <stdint.h> typedef int8_t vnx2qi __attribute__ ((vector_size (2))); #define MASK_2(X, Y) (Y) - 1 - (X), (Y) - 2 - (X) #define PERMUTE(TYPE, NUNITS) \ __attribute__ ((noipa)) void permute_##TYPE (TYPE values1, TYPE values2, \ TYPE *out) \ { \ TYPE v \ = __builtin_shufflevector (values1, values2, MASK_##NUNITS (0, NUNITS)); \ *(TYPE *) out = v; \ } #define TEST_ALL(T) \ T (vnx2qi, 2) TEST_ALL (PERMUTE) Before this patch: vsetivli zero,2,e8,mf8,ta,ma vle8.v v1,0(a0) vsetivli zero,1,e16,mf4,ta,ma vsrl.vi v2,v1,8 vsll.vi v1,v1,8 vor.vv v1,v2,v1 vsetivli zero,2,e8,mf8,ta,ma vse8.v v1,0(a2) ret After this patch: vsetivli zero,2,e8,mf8,ta,ma vle8.v v3,0(a0) vid.v v1 vrsub.vi v1,v1,1 vrgather.vv v2,v3,v1 vse8.v v2,0(a2) ret Committed as it is very obvious if during code review. gcc/ChangeLog: * config/riscv/riscv-v.cc (shuffle_bswap_pattern): Disable for NUNIT < 4. gcc/testsuite/ChangeLog: * gcc.target/riscv/rvv/autovec/vls-vlmax/perm-4.c: Adapt test. * gcc.target/riscv/rvv/autovec/vls/perm-4.c: Ditto. --- gcc/config/riscv/riscv-v.cc | 5 +++++ .../gcc.target/riscv/rvv/autovec/vls-vlmax/perm-4.c | 4 ++-- gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/perm-4.c | 4 ++-- 3 files changed, 9 insertions(+), 4 deletions(-) diff --git a/gcc/config/riscv/riscv-v.cc b/gcc/config/riscv/riscv-v.cc index 18619a11592..4bd1131ba87 100644 --- a/gcc/config/riscv/riscv-v.cc +++ b/gcc/config/riscv/riscv-v.cc @@ -3201,6 +3201,11 @@ shuffle_bswap_pattern (struct expand_vec_perm_d *d) if (!d->perm.series_p (i, step, diff - i, step)) return false; + /* Disable when nunits < 4 since the later generic approach + is more profitable on BSWAP. */ + if (!known_gt (GET_MODE_NUNITS (d->vmode), 2)) + return false; + if (d->testing_p) return true; diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/perm-4.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/perm-4.c index b235ec727b1..7ab31043547 100644 --- a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/perm-4.c +++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls-vlmax/perm-4.c @@ -55,7 +55,7 @@ TEST_ALL (PERMUTE) -/* { dg-final { scan-assembler-times {vrgather\.vv\tv[0-9]+,\s*v[0-9]+,\s*v[0-9]+} 18 } } */ +/* { dg-final { scan-assembler-times {vrgather\.vv\tv[0-9]+,\s*v[0-9]+,\s*v[0-9]+} 19 } } */ /* { dg-final { scan-assembler-times {vrgatherei16\.vv\tv[0-9]+,\s*v[0-9]+,\s*v[0-9]+} 12 } } */ -/* { dg-final { scan-assembler-times {vrsub\.vi} 23 } } */ +/* { dg-final { scan-assembler-times {vrsub\.vi} 24 } } */ /* { dg-final { scan-assembler-times {vrsub\.vx} 7 } } */ diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/perm-4.c b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/perm-4.c index d2d49388a39..4d6862cf1c0 100644 --- a/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/perm-4.c +++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/vls/perm-4.c @@ -3,7 +3,7 @@ #include "../vls-vlmax/perm-4.c" -/* { dg-final { scan-assembler-times {vrgather\.vv\tv[0-9]+,\s*v[0-9]+,\s*v[0-9]+} 18 } } */ +/* { dg-final { scan-assembler-times {vrgather\.vv\tv[0-9]+,\s*v[0-9]+,\s*v[0-9]+} 19 } } */ /* { dg-final { scan-assembler-times {vrgatherei16\.vv\tv[0-9]+,\s*v[0-9]+,\s*v[0-9]+} 12 } } */ -/* { dg-final { scan-assembler-times {vrsub\.vi} 23 } } */ +/* { dg-final { scan-assembler-times {vrsub\.vi} 24 } } */ /* { dg-final { scan-assembler-times {vrsub\.vx} 7 } } */ -- 2.36.3