[FFmpeg-devel,v2,1/7] avutil: [loongarch] Add support for loongarch SIMD.

diff --git a/Makefile b/Makefile
index 26c9107237..5b20658b52 100644
--- a/Makefile
+++ b/Makefile
@@ -89,7 +89,7 @@  SUBDIR_VARS := CLEANFILES FFLIBS HOSTPROGS TESTPROGS TOOLS               \
                ARMV5TE-OBJS ARMV6-OBJS ARMV8-OBJS VFP-OBJS NEON-OBJS     \
                ALTIVEC-OBJS VSX-OBJS MMX-OBJS X86ASM-OBJS                \
                MIPSFPU-OBJS MIPSDSPR2-OBJS MIPSDSP-OBJS MSA-OBJS         \
-               MMI-OBJS OBJS SLIBOBJS HOSTOBJS TESTOBJS
+               MMI-OBJS LSX-OBJS LASX-OBJS OBJS SLIBOBJS HOSTOBJS TESTOBJS
 
 define RESET
 $(1) :=
diff --git a/configure b/configure
index a7593ec2db..c4afde4c5c 100755
--- a/configure
+++ b/configure
@@ -452,7 +452,9 @@  Optimization options (experts only):
   --disable-mipsdspr2      disable MIPS DSP ASE R2 optimizations
   --disable-msa            disable MSA optimizations
   --disable-mipsfpu        disable floating point MIPS optimizations
-  --disable-mmi            disable Loongson SIMD optimizations
+  --disable-mmi            disable Loongson MMI optimizations
+  --disable-lsx            disable Loongson LSX optimizations
+  --disable-lasx           disable Loongson LASX optimizations
   --disable-fast-unaligned consider unaligned accesses slow
 
 Developer options (useful when working on FFmpeg itself):
@@ -2081,6 +2083,8 @@  ARCH_EXT_LIST_LOONGSON="
     loongson2
     loongson3
     mmi
+    lsx
+    lasx
 "
 
 ARCH_EXT_LIST_X86_SIMD="
@@ -2617,6 +2621,10 @@  power8_deps="vsx"
 
 loongson2_deps="mips"
 loongson3_deps="mips"
+mmi_deps_any="loongson2 loongson3"
+lsx_deps="loongarch"
+lasx_deps="lsx"
+
 mips32r2_deps="mips"
 mips32r5_deps="mips"
 mips32r6_deps="mips"
@@ -2625,7 +2633,6 @@  mips64r6_deps="mips"
 mipsfpu_deps="mips"
 mipsdsp_deps="mips"
 mipsdspr2_deps="mips"
-mmi_deps_any="loongson2 loongson3"
 msa_deps="mipsfpu"
 
 cpunop_deps="i686"
@@ -6134,6 +6141,9 @@  EOF
         ;;
     esac
 
+elif enabled loongarch; then
+    enabled lsx && check_inline_asm lsx '"vadd.b $vr0, $vr1, $vr2"' '-mlsx' && append LSXFLAGS '-mlsx'
+    enabled lasx && check_inline_asm lasx '"xvadd.b $xr0, $xr1, $xr2"' '-mlasx' && append LASXFLAGS '-mlasx'
 fi
 
 check_cc intrinsics_neon arm_neon.h "int16x8_t test = vdupq_n_s16(0)"
@@ -7484,6 +7494,10 @@  if enabled ppc; then
     echo "PPC 4xx optimizations     ${ppc4xx-no}"
     echo "dcbzl available           ${dcbzl-no}"
 fi
+if enabled loongarch; then
+    echo "LSX enabled               ${lsx-no}"
+    echo "LASX enabled              ${lasx-no}"
+fi
 echo "debug symbols             ${debug-no}"
 echo "strip symbols             ${stripping-no}"
 echo "optimize for size         ${small-no}"
@@ -7645,6 +7659,8 @@  ASMSTRIPFLAGS=$ASMSTRIPFLAGS
 X86ASMFLAGS=$X86ASMFLAGS
 MSAFLAGS=$MSAFLAGS
 MMIFLAGS=$MMIFLAGS
+LSXFLAGS=$LSXFLAGS
+LASXFLAGS=$LASXFLAGS
 BUILDSUF=$build_suffix
 PROGSSUF=$progs_suffix
 FULLNAME=$FULLNAME
diff --git a/ffbuild/arch.mak b/ffbuild/arch.mak
index e09006efca..997e31e85e 100644
--- a/ffbuild/arch.mak
+++ b/ffbuild/arch.mak
@@ -8,7 +8,9 @@  OBJS-$(HAVE_MIPSFPU)   += $(MIPSFPU-OBJS)    $(MIPSFPU-OBJS-yes)
 OBJS-$(HAVE_MIPSDSP)   += $(MIPSDSP-OBJS)    $(MIPSDSP-OBJS-yes)
 OBJS-$(HAVE_MIPSDSPR2) += $(MIPSDSPR2-OBJS)  $(MIPSDSPR2-OBJS-yes)
 OBJS-$(HAVE_MSA)       += $(MSA-OBJS)        $(MSA-OBJS-yes)
-OBJS-$(HAVE_MMI)   += $(MMI-OBJS)   $(MMI-OBJS-yes)
+OBJS-$(HAVE_MMI)       += $(MMI-OBJS)        $(MMI-OBJS-yes)
+OBJS-$(HAVE_LSX)       += $(LSX-OBJS)        $(LSX-OBJS-yes)
+OBJS-$(HAVE_LASX)      += $(LASX-OBJS)       $(LASX-OBJS-yes)
 
 OBJS-$(HAVE_ALTIVEC) += $(ALTIVEC-OBJS) $(ALTIVEC-OBJS-yes)
 OBJS-$(HAVE_VSX)     += $(VSX-OBJS) $(VSX-OBJS-yes)
diff --git a/ffbuild/common.mak b/ffbuild/common.mak
index 268ae61154..0eb831d434 100644
--- a/ffbuild/common.mak
+++ b/ffbuild/common.mak
@@ -59,6 +59,8 @@  COMPILE_HOSTC = $(call COMPILE,HOSTCC)
 COMPILE_NVCC = $(call COMPILE,NVCC)
 COMPILE_MMI = $(call COMPILE,CC,MMIFLAGS)
 COMPILE_MSA = $(call COMPILE,CC,MSAFLAGS)
+COMPILE_LSX = $(call COMPILE,CC,LSXFLAGS)
+COMPILE_LASX = $(call COMPILE,CC,LASXFLAGS)
 
 %_mmi.o: %_mmi.c
 	$(COMPILE_MMI)
@@ -66,6 +68,12 @@  COMPILE_MSA = $(call COMPILE,CC,MSAFLAGS)
 %_msa.o: %_msa.c
 	$(COMPILE_MSA)
 
+%_lsx.o: %_lsx.c
+	$(COMPILE_LSX)
+
+%_lasx.o: %_lasx.c
+	$(COMPILE_LASX)
+
 %.o: %.c
 	$(COMPILE_C)
 
diff --git a/libavutil/cpu.c b/libavutil/cpu.c
index 4627af4f23..63efb97ffd 100644
--- a/libavutil/cpu.c
+++ b/libavutil/cpu.c
@@ -62,6 +62,8 @@  static int get_cpu_flags(void)
         return ff_get_cpu_flags_ppc();
     if (ARCH_X86)
         return ff_get_cpu_flags_x86();
+    if (ARCH_LOONGARCH)
+        return ff_get_cpu_flags_loongarch();
     return 0;
 }
 
@@ -168,6 +170,9 @@  int av_parse_cpu_caps(unsigned *flags, const char *s)
 #elif ARCH_MIPS
         { "mmi",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MMI      },    .unit = "flags" },
         { "msa",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MSA      },    .unit = "flags" },
+#elif ARCH_LOONGARCH
+        { "lsx",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_LSX      },    .unit = "flags" },
+        { "lasx",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_LASX     },    .unit = "flags" },
 #endif
         { NULL },
     };
@@ -253,6 +258,8 @@  size_t av_cpu_max_align(void)
         return ff_get_cpu_max_align_ppc();
     if (ARCH_X86)
         return ff_get_cpu_max_align_x86();
+    if (ARCH_LOONGARCH)
+        return ff_get_cpu_max_align_loongarch();
 
     return 8;
 }
diff --git a/libavutil/cpu.h b/libavutil/cpu.h
index afea0640b4..ae443eccad 100644
--- a/libavutil/cpu.h
+++ b/libavutil/cpu.h
@@ -72,6 +72,10 @@ 
 #define AV_CPU_FLAG_MMI          (1 << 0)
 #define AV_CPU_FLAG_MSA          (1 << 1)
 
+//Loongarch SIMD extension.
+#define AV_CPU_FLAG_LSX          (1 << 0)
+#define AV_CPU_FLAG_LASX         (1 << 1)
+
 /**
  * Return the flags which specify extensions supported by the CPU.
  * The returned value is affected by av_force_cpu_flags() if that was used
diff --git a/libavutil/cpu_internal.h b/libavutil/cpu_internal.h
index 889764320b..e207b2d480 100644
--- a/libavutil/cpu_internal.h
+++ b/libavutil/cpu_internal.h
@@ -46,11 +46,13 @@  int ff_get_cpu_flags_aarch64(void);
 int ff_get_cpu_flags_arm(void);
 int ff_get_cpu_flags_ppc(void);
 int ff_get_cpu_flags_x86(void);
+int ff_get_cpu_flags_loongarch(void);
 
 size_t ff_get_cpu_max_align_mips(void);
 size_t ff_get_cpu_max_align_aarch64(void);
 size_t ff_get_cpu_max_align_arm(void);
 size_t ff_get_cpu_max_align_ppc(void);
 size_t ff_get_cpu_max_align_x86(void);
+size_t ff_get_cpu_max_align_loongarch(void);
 
 #endif /* AVUTIL_CPU_INTERNAL_H */
diff --git a/libavutil/loongarch/Makefile b/libavutil/loongarch/Makefile
new file mode 100644
index 0000000000..2addd9351c
--- /dev/null
+++ b/libavutil/loongarch/Makefile
@@ -0,0 +1 @@ 
+OBJS += loongarch/cpu.o
diff --git a/libavutil/loongarch/cpu.c b/libavutil/loongarch/cpu.c
new file mode 100644
index 0000000000..e4b240bc44
--- /dev/null
+++ b/libavutil/loongarch/cpu.c
@@ -0,0 +1,69 @@ 
+/*
+ * Copyright (c) 2020 Loongson Technology Corporation Limited
+ * Contributed by Shiyou Yin <yinshiyou-hf@loongson.cn>
+ *
+ * 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 <stdint.h>
+#include "cpu.h"
+
+#define LOONGARCH_CFG2 0x2
+#define LOONGARCH_CFG2_LSX    (1 << 6)
+#define LOONGARCH_CFG2_LASX   (1 << 7)
+
+static int cpu_flags_cpucfg(void)
+{
+    int flags = 0;
+    uint32_t cfg2 = 0;
+
+    __asm__ volatile(
+        "cpucfg %0, %1 \n\t"
+        : "+&r"(cfg2)
+        : "r"(LOONGARCH_CFG2)
+    );
+
+    if (cfg2 & LOONGARCH_CFG2_LSX)
+        flags |= AV_CPU_FLAG_LSX;
+
+    if (cfg2 & LOONGARCH_CFG2_LASX)
+        flags |= AV_CPU_FLAG_LASX;
+
+    return flags;
+}
+
+int ff_get_cpu_flags_loongarch(void)
+{
+#if defined __linux__
+    return cpu_flags_cpucfg();
+#else
+    /* Assume no SIMD ASE supported */
+    return 0;
+#endif
+}
+
+size_t ff_get_cpu_max_align_loongarch(void)
+{
+    int flags = av_get_cpu_flags();
+
+    if (flags & AV_CPU_FLAG_LASX)
+        return 32;
+    if (flags & AV_CPU_FLAG_LSX)
+        return 16;
+
+    return 8;
+}
diff --git a/libavutil/loongarch/cpu.h b/libavutil/loongarch/cpu.h
new file mode 100644
index 0000000000..1a445c69bc
--- /dev/null
+++ b/libavutil/loongarch/cpu.h
@@ -0,0 +1,31 @@ 
+/*
+ * Copyright (c) 2020 Loongson Technology Corporation Limited
+ * Contributed by Shiyou Yin <yinshiyou-hf@loongson.cn>
+ *
+ * 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
+ */
+
+#ifndef AVUTIL_LOONGARCH_CPU_H
+#define AVUTIL_LOONGARCH_CPU_H
+
+#include "libavutil/cpu.h"
+#include "libavutil/cpu_internal.h"
+
+#define have_lsx(flags) CPUEXT(flags, LSX)
+#define have_lasx(flags) CPUEXT(flags, LASX)
+
+#endif /* AVUTIL_LOONGARCH_CPU_H */
diff --git a/libavutil/tests/cpu.c b/libavutil/tests/cpu.c
index c853371fb3..0a6c0cd32e 100644
--- a/libavutil/tests/cpu.c
+++ b/libavutil/tests/cpu.c
@@ -77,6 +77,9 @@  static const struct {
     { AV_CPU_FLAG_BMI2,      "bmi2"       },
     { AV_CPU_FLAG_AESNI,     "aesni"      },
     { AV_CPU_FLAG_AVX512,    "avx512"     },
+#elif ARCH_LOONGARCH
+    { AV_CPU_FLAG_LSX,       "lsx"        },
+    { AV_CPU_FLAG_LASX,      "lasx"       },
 #endif
     { 0 }
 };
diff --git a/tests/checkasm/checkasm.c b/tests/checkasm/checkasm.c
index b1353f7cbe..90d080de02 100644
--- a/tests/checkasm/checkasm.c
+++ b/tests/checkasm/checkasm.c
@@ -236,6 +236,9 @@  static const struct {
     { "FMA4",     "fma4",     AV_CPU_FLAG_FMA4 },
     { "AVX2",     "avx2",     AV_CPU_FLAG_AVX2 },
     { "AVX-512",  "avx512",   AV_CPU_FLAG_AVX512 },
+#elif ARCH_LOONGARCH
+    { "LSX",      "lsx",      AV_CPU_FLAG_LSX },
+    { "LASX",     "lasx",     AV_CPU_FLAG_LASX },
 #endif
     { NULL }
 };