| Message ID | 20220903123559.78526-1-remi@remlab.net |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel] riscv: detect fast CLZ from Zbb extension | expand |
| Context | Check | Description |
|---|---|---|
| yinshiyou/make_loongarch64 | success | Make finished |
| yinshiyou/make_fate_loongarch64 | success | Make fate finished |
| andriy/make_x86 | success | Make finished |
| andriy/make_fate_x86 | success | Make fate finished |
diff --git a/configure b/configure index 932ea5b553..b54ff5fc44 100755 --- a/configure +++ b/configure @@ -5331,6 +5331,12 @@ elif enabled ppc; then ;; esac +elif enabled riscv; then + + if test_cpp_condition stddef.h "__riscv_zbb"; then + enable fast_clz + fi + elif enabled sparc; then case $cpu in
From: Rémi Denis-Courmont <remi@remlab.net> RISC-V defines the CLZ instruction as part of the Zbb subset of the bit mapulation extension (B). We can detect it from the __riscv_zbb predefined constant. It will be non-zero if supported, zero if enabled in the compiler flags but not supported by the compiler, and undefined otherwise. --- configure | 6 ++++++ 1 file changed, 6 insertions(+)