From cdfafb3426cdf3a6c60fe2e20eb52c72d2777e51 Mon Sep 17 00:00:00 2001
From: WangXiang <KatyushaScarlet@Outlook.com>
Date: Sun, 10 Dec 2023 23:04:32 +0800
Subject: [PATCH] Add loongarch64 support

Adding support for LoongArch64 architecture. Tested on Loongson 3A6000 EVB
Board. Since Loongson's SIMD extended instruction set
([LSX](https://gcc.gnu.org/onlinedocs/gcc/LoongArch-SX-Vector-Intrinsics.html),
[LASX](https://gcc.gnu.org/onlinedocs/gcc/LoongArch-ASX-Vector-Intrinsics.html))
is already supported by GCC, more optimizations are being developed.

Here's the benchmark result for Loongson 3A6000 (4c8t, 2.5Ghz) without SIMD
optimizations.
```
Total time (ms) : 17903
Nodes searched  : 1244386
Nodes/second    : 69507
```

closes https://github.com/official-stockfish/Stockfish/pull/4913

No functional change
---
 AUTHORS      |  1 +
 src/Makefile | 13 +++++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/AUTHORS b/AUTHORS
index d7b64b62..f6a10288 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -227,6 +227,7 @@ Vince Negri (cuddlestmonkey)
 Viren
 windfishballad
 xefoci7612
+Xiang Wang (KatyushaScarlet)
 zz4032
 
 # Additionally, we acknowledge the authors and maintainers of fishtest,
diff --git a/src/Makefile b/src/Makefile
index 59ea7bfe..761b4086 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -125,7 +125,7 @@ ifeq ($(ARCH), $(filter $(ARCH), \
                  x86-64-vnni512 x86-64-vnni256 x86-64-avx512 x86-64-avxvnni x86-64-bmi2 \
                  x86-64-avx2 x86-64-sse41-popcnt x86-64-modern x86-64-ssse3 x86-64-sse3-popcnt \
                  x86-64 x86-32-sse41-popcnt x86-32-sse2 x86-32 ppc-64 ppc-32 e2k \
-                 armv7 armv7-neon armv8 armv8-dotprod apple-silicon general-64 general-32 riscv64))
+                 armv7 armv7-neon armv8 armv8-dotprod apple-silicon general-64 general-32 riscv64 loongarch64))
    SUPPORTED_ARCH=true
 else
    SUPPORTED_ARCH=false
@@ -369,6 +369,10 @@ endif
 ifeq ($(ARCH),riscv64)
 	arch = riscv64
 endif
+
+ifeq ($(ARCH),loongarch64)
+	arch = loongarch64
+endif
 endif
 
 
@@ -404,6 +408,8 @@ ifeq ($(COMP),gcc)
 		ifeq ($(ARCH),riscv64)
 			CXXFLAGS += -latomic
 		endif
+	else ifeq ($(ARCH),loongarch64)
+		CXXFLAGS += -latomic
 	else
 		CXXFLAGS += -m$(bits)
 		LDFLAGS += -m$(bits)
@@ -474,6 +480,8 @@ ifeq ($(COMP),clang)
 		ifeq ($(ARCH),riscv64)
 			CXXFLAGS += -latomic
 		endif
+	else ifeq ($(ARCH),loongarch64)
+		CXXFLAGS += -latomic
 	else
 		CXXFLAGS += -m$(bits)
 		LDFLAGS += -m$(bits)
@@ -823,6 +831,7 @@ help:
 	@echo "general-64              > unspecified 64-bit"
 	@echo "general-32              > unspecified 32-bit"
 	@echo "riscv64                 > RISC-V 64-bit"
+	@echo "loongarch64             > LoongArch 64-bit"
 	@echo ""
 	@echo "Supported compilers:"
 	@echo ""
@@ -1004,7 +1013,7 @@ config-sanity: net
 	@test "$(SUPPORTED_ARCH)" = "true"
 	@test "$(arch)" = "any" || test "$(arch)" = "x86_64" || test "$(arch)" = "i386" || \
 	 test "$(arch)" = "ppc64" || test "$(arch)" = "ppc" || test "$(arch)" = "e2k" || \
-	 test "$(arch)" = "armv7" || test "$(arch)" = "armv8" || test "$(arch)" = "arm64" || test "$(arch)" = "riscv64"
+	 test "$(arch)" = "armv7" || test "$(arch)" = "armv8" || test "$(arch)" = "arm64" || test "$(arch)" = "riscv64" || test "$(arch)" = "loongarch64"
 	@test "$(bits)" = "32" || test "$(bits)" = "64"
 	@test "$(prefetch)" = "yes" || test "$(prefetch)" = "no"
 	@test "$(popcnt)" = "yes" || test "$(popcnt)" = "no"
-- 
2.39.2