lavu/riscv: initial common header for assembler macros

libavutil/riscv/asm.S

@@ -0,0 +1,77 @@
+/*
+ * Copyright © 2022 Rémi Denis-Courmont.
+ * Loosely based on earlier work copyrighted by Måns Rullgård, 2008.
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "config.h"
+
+#if defined (__riscv_float_abi_soft)
+#define NOHWF
+#define NOHWD
+#define HWF   #
+#define HWD   #
+#elif defined (__riscv_float_abi_single)
+#define NOHWF #
+#define NOHWD
+#define HWF
+#define HWD   #
+#else
+#define NOHWF #
+#define NOHWD #
+#define HWF
+#define HWD
+#endif
+
+        .macro func sym, ext=
+            .text
+            .align 2
+
+            .option push
+            .ifnb \ext
+            .option arch, +\ext
+            .endif
+
+            .global \sym
+            .hidden \sym
+            .type   \sym, %function
+            \sym:
+
+            .macro endfunc
+                .size   \sym, . - \sym
+                .option pop
+                .previous
+                .purgem endfunc
+            .endm
+        .endm
+
+        .macro const sym, align=3, relocate=0
+            .if \relocate
+                .pushsection .data.rel.ro
+            .else
+                .pushsection .rodata
+            .endif
+            .align \align
+            \sym:
+
+            .macro endconst
+                .size  \sym, . - \sym
+                .popsection
+                .purgem endconst
+            .endm
+        .endm