arm: Check for the .arch directive in configure

Message ID 1493887532-27087-1-git-send-email-martin@martin.st
State Committed
Commit 59cee42d7d22530e66a155305389e29679b11f78
Headers show

Commit Message

Martin Storsjö May 4, 2017, 8:45 a.m.
When targeting windows, the .arch directive isn't available.

So far, when building for windows, we've always used gas-preprocessor,
both when using msvc's armasm and when using clang. Lately, clang/llvm
has implemented the last missing piece (altmacro support) for building
our assembly without gas-preprocessor. This means that we now build
for arm/windows with clang without any extra compatibility layer.
---
Updated to use a plain ifdef guard around the block instead of introducing
a line prefix as for e.g. ELF (since this is the only place where .arch
is used), as suggested by Janne on irc.
---
 configure           | 4 ++++
 libavutil/arm/asm.S | 2 ++
 2 files changed, 6 insertions(+)

Comments

Luca Barbato May 4, 2017, 10:11 a.m. | #1
On 5/4/17 10:45 AM, Martin Storsjö wrote:
> is used), as suggested by Janne on irc.

Looks fine.

Patch

diff --git a/configure b/configure
index c7d0363..029ae9e 100755
--- a/configure
+++ b/configure
@@ -1661,6 +1661,7 @@  SYSTEM_FUNCS="
 "
 
 TOOLCHAIN_FEATURES="
+    as_arch_directive
     as_dn_directive
     as_fpu_directive
     as_func
@@ -4372,6 +4373,9 @@  EOF
 
     check_inline_asm asm_mod_q '"add r0, %Q0, %R0" :: "r"((long long)0)'
 
+    check_as <<EOF && enable as_arch_directive
+.arch armv7-a
+EOF
     check_as <<EOF && enable as_dn_directive
 ra .dn d0.i16
 .unreq ra
diff --git a/libavutil/arm/asm.S b/libavutil/arm/asm.S
index a791e80..0857485 100644
--- a/libavutil/arm/asm.S
+++ b/libavutil/arm/asm.S
@@ -46,6 +46,7 @@ 
 #   define FPU @
 #endif
 
+#if HAVE_AS_ARCH_DIRECTIVE
 #if   HAVE_NEON
         .arch           armv7-a
 #elif HAVE_ARMV6T2
@@ -55,6 +56,7 @@ 
 #elif HAVE_ARMV5TE
         .arch           armv5te
 #endif
+#endif
 #if   HAVE_AS_OBJECT_ARCH
 ELF     .object_arch    armv4
 #endif