[FFmpeg-devel] [PATCH] configure: Remove dcbzl check for e500v1 and e500v2 architectures

[Rémi Denis-Courmont]

Le 26 septembre 2022 13:51:44 GMT+03:00, Peter Krefting <peter at softwolves.pp.se> a écrit :
>The DCBZL instruction is not available for the e500v1 and e500v2
>architectures, but may still be recognized by the toolchain, so we need to
>remove the test for it explicitly for these architectures.

Isn't this the sort of thing that's supposed ti be guarded by run-time CPU flags rather than in the configure script?

>References: PowerPC™ e500 Core Family Reference Manual (Freescale)
>
>Found-by: Ståle Kristoffersen <staalebk at ifi.uio.no>
>Compare: Commit d5733936d857ce5c7d28c0bc9e89a2e2548f8895
>---
> configure | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
>This was originally fixed by commit d5733936d857ce5c7d28c0bc9e89a2e2548f8895
>in version 2.2, but later broke in a merge which introduced a "disable dcbzl",
>forgot to check for it in the ppc branch.
>
>diff --git a/configure b/configure
>index 7a62f0c248..5d01833f40 100755
>--- a/configure
>+++ b/configure
>@@ -6058,7 +6058,9 @@ elif enabled ppc; then
>
>     enable local_aligned
>
>-    check_inline_asm dcbzl     '"dcbzl 0, %0" :: "r"(0)'
>+    if enabled dcbzl; then
>+        check_inline_asm dcbzl    '"dcbzl 0, %0" :: "r"(0)'
>+    fi
>     check_inline_asm ibm_asm   '"add 0, 0, 0"'
>     check_inline_asm ppc4xx    '"maclhw r10, r11, r12"'
>     check_inline_asm xform_asm '"lwzx %1, %y0" :: "Z"(*(int*)0), "r"(0)'