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| author | Rémi Denis-Courmont <remi@remlab.net> | 2022-10-05 19:12:54 +0300 |
|---|---|---|
| committer | Lynne <dev@lynne.ee> | 2022-10-10 02:22:12 +0200 |
| commit | f59a767ccd56ba1b82ae94e2229f9151936f8b7c (patch) | |
| tree | e8bdb02a278a3895ca6e5db1e4dc1a89fce28069 | |
| parent | 8009581912d0e5d6ecfa650cd0ce90c58c515b69 (diff) | |
| download | ffmpeg-f59a767ccd56ba1b82ae94e2229f9151936f8b7c.tar.gz | |
lavu/riscv: helper macro for VTYPE encoding
On most cases, the vector type (VTYPE) for the RISC-V Vector extension
is supplied as an immediate value, with either of the VSETVLI or
VSETIVLI instructions. There is however a third instruction VSETVL
which takes the vector type from a general purpose register. That is so
the type can be selected at run-time.
This introduces a macro to load a (valid) vector type into a register.
The syntax follows that of VSETVLI and VSETIVLI, with element size,
group multiplier, then tail and mask policies.
| -rw-r--r-- | libavutil/riscv/asm.S | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/libavutil/riscv/asm.S b/libavutil/riscv/asm.S index ffa0bd9068..6ca74f263a 100644 --- a/libavutil/riscv/asm.S +++ b/libavutil/riscv/asm.S @@ -92,3 +92,78 @@ shnadd 3, \rd, \rs1, \rs2 .endm #endif + + /* Convenience macro to load a Vector type (vtype) as immediate */ + .macro lvtypei rd, e, m=m1, tp=tu, mp=mu + + .ifc \e,e8 + .equ ei, 0 + .else + .ifc \e,e16 + .equ ei, 8 + .else + .ifc \e,e32 + .equ ei, 16 + .else + .ifc \e,e64 + .equ ei, 24 + .else + .error "Unknown element type" + .endif + .endif + .endif + .endif + + .ifc \m,m1 + .equ mi, 0 + .else + .ifc \m,m2 + .equ mi, 1 + .else + .ifc \m,m4 + .equ mi, 2 + .else + .ifc \m,m8 + .equ mi, 3 + .else + .ifc \m,mf8 + .equ mi, 5 + .else + .ifc \m,mf4 + .equ mi, 6 + .else + .ifc \m,mf2 + .equ mi, 7 + .else + .error "Unknown multiplier" + .equ mi, 3 + .endif + .endif + .endif + .endif + .endif + .endif + .endif + + .ifc \tp,tu + .equ tpi, 0 + .else + .ifc \tp,ta + .equ tpi, 64 + .else + .error "Unknown tail policy" + .endif + .endif + + .ifc \mp,mu + .equ mpi, 0 + .else + .ifc \mp,ma + .equ mpi, 128 + .else + .error "Unknown mask policy" + .endif + .endif + + li \rd, (ei | mi | tpi | mpi) + .endm |