[Bug target/108654] Incorrect codegen of RVV GCC
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108654 JuzheZhong changed: What|Removed |Added Resolution|--- |FIXED Status|UNCONFIRMED |RESOLVED --- Comment #4 from JuzheZhong --- Fixed
[Bug target/108654] Incorrect codegen of RVV GCC
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108654 --- Comment #3 from JuzheZhong --- FIXED
[Bug target/108654] Incorrect codegen of RVV GCC
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108654
--- Comment #2 from CVS Commits ---
The master branch has been updated by Kito Cheng :
https://gcc.gnu.org/g:3a982e07d28a46da81ee5b65b03a896d84b32a48
commit r13-6826-g3a982e07d28a46da81ee5b65b03a896d84b32a48
Author: Pan Li
Date: Wed Mar 8 15:33:33 2023 +0800
RISC-V: Bugfix for rvv bool mode size adjustment
Fix the bug of the rvv bool mode size by the adjustment.
Besides the mode precision (aka bit size [1, 2, 4, 8, 16, 32, 64])
of the vbool*_t, the mode size (aka byte size) will be adjusted to
[1, 1, 1, 1, 2, 4, 8] according to the rvv spec 1.0 isa. The
adjustment will provide correct information for the underlying
redundant instruction elimiation.
Given the below sample code:
{
vbool1_t v1 = *(vbool1_t*)in;
vbool64_t v2 = *(vbool64_t*)in;
*(vbool1_t*)(out + 100) = v1;
*(vbool64_t*)(out + 200) = v2;
}
Before the size adjustment:
csrrt0,vlenb
sllit1,t0,1
csrra3,vlenb
sub sp,sp,t1
sllia4,a3,1
add a4,a4,sp
addia2,a1,100
vsetvli a5,zero,e8,m8,ta,ma
sub a3,a4,a3
vlm.v v24,0(a0)
vsm.v v24,0(a2)
vsm.v v24,0(a3)
addia1,a1,200
csrrt0,vlenb
vsetvli a4,zero,e8,mf8,ta,ma
sllit1,t0,1
vlm.v v24,0(a3)
vsm.v v24,0(a1)
add sp,sp,t1
jr ra
After the size adjustment:
addia3,a1,100
vsetvli a4,zero,e8,m8,ta,ma
addia1,a1,200
vlm.v v24,0(a0)
vsm.v v24,0(a3)
vsetvli a5,zero,e8,mf8,ta,ma
vlm.v v24,0(a0)
vsm.v v24,0(a1)
ret
Additionally, the size adjust cannot cover all possible combinations
of the vbool*_t code pattern like above. We will take a look into it
in another patches.
PR 108185
PR 108654
gcc/ChangeLog:
PR target/108654
PR target/108185
* config/riscv/riscv-modes.def (ADJUST_BYTESIZE): Adjust size
for vector mask modes.
* config/riscv/riscv.cc (riscv_v_adjust_bytesize): New.
* config/riscv/riscv.h (riscv_v_adjust_bytesize): New.
gcc/testsuite/ChangeLog:
PR target/108654
PR target/108185
* gcc.target/riscv/rvv/base/pr108185-1.c: Update.
* gcc.target/riscv/rvv/base/pr108185-2.c: Ditto.
* gcc.target/riscv/rvv/base/pr108185-3.c: Ditto.
Signed-off-by: Pan Li
Co-authored-by: Ju-Zhe Zhong
[Bug target/108654] Incorrect codegen of RVV GCC
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108654
--- Comment #1 from CVS Commits ---
The master branch has been updated by Kito Cheng :
https://gcc.gnu.org/g:247cacc9e381d666a492dfa4ed61b7b19e2d008f
commit r13-6524-g247cacc9e381d666a492dfa4ed61b7b19e2d008f
Author: Pan Li
Date: Tue Mar 7 20:05:15 2023 +0800
RISC-V: Bugfix for rvv bool mode precision adjustment
Fix the bug of the rvv bool mode precision with the adjustment.
The bits size of vbool*_t will be adjusted to
[1, 2, 4, 8, 16, 32, 64] according to the rvv spec 1.0 isa. The
adjusted mode precison of vbool*_t will help underlying pass to
make the right decision for both the correctness and optimization.
Given below sample code:
void test_1(int8_t * restrict in, int8_t * restrict out)
{
vbool8_t v2 = *(vbool8_t*)in;
vbool16_t v5 = *(vbool16_t*)in;
*(vbool16_t*)(out + 200) = v5;
*(vbool8_t*)(out + 100) = v2;
}
Before the precision adjustment:
addia4,a1,100
vsetvli a5,zero,e8,m1,ta,ma
addia1,a1,200
vlm.v v24,0(a0)
vsm.v v24,0(a4)
// Need one vsetvli and vlm.v for correctness here.
vsm.v v24,0(a1)
After the precision adjustment:
csrrt0,vlenb
sllit1,t0,1
csrra3,vlenb
sub sp,sp,t1
sllia4,a3,1
add a4,a4,sp
sub a3,a4,a3
vsetvli a5,zero,e8,m1,ta,ma
addia2,a1,200
vlm.v v24,0(a0)
vsm.v v24,0(a3)
addia1,a1,100
vsetvli a4,zero,e8,mf2,ta,ma
csrrt0,vlenb
vlm.v v25,0(a3)
vsm.v v25,0(a2)
sllit1,t0,1
vsetvli a5,zero,e8,m1,ta,ma
vsm.v v24,0(a1)
add sp,sp,t1
jr ra
However, there may be some optimization opportunates after
the mode precision adjustment. It can be token care of in
the RISC-V backend in the underlying separted PR(s).
gcc/ChangeLog:
PR target/108185
PR target/108654
* config/riscv/riscv-modes.def (ADJUST_PRECISION): Adjust VNx*BI
modes.
* config/riscv/riscv.cc (riscv_v_adjust_precision): New.
* config/riscv/riscv.h (riscv_v_adjust_precision): New.
* genmodes.cc (adj_precision): New.
(ADJUST_PRECISION): New.
(emit_mode_adjustments): Handle ADJUST_PRECISION.
gcc/testsuite/ChangeLog:
PR target/108185
PR target/108654
* gcc.target/riscv/rvv/base/pr108185-1.c: New test.
* gcc.target/riscv/rvv/base/pr108185-2.c: New test.
* gcc.target/riscv/rvv/base/pr108185-3.c: New test.
* gcc.target/riscv/rvv/base/pr108185-4.c: New test.
* gcc.target/riscv/rvv/base/pr108185-5.c: New test.
* gcc.target/riscv/rvv/base/pr108185-6.c: New test.
* gcc.target/riscv/rvv/base/pr108185-7.c: New test.
* gcc.target/riscv/rvv/base/pr108185-8.c: New test.
Signed-off-by: Pan Li
Co-authored-by: Ju-Zhe Zhong
