diff --git a/Source/JavaScriptCore/CMakeLists.txt b/Source/JavaScriptCore/CMakeLists.txt

index afd76ca1a..3fca6e049 100644

--- a/Source/JavaScriptCore/CMakeLists.txt

+++ b/Source/JavaScriptCore/CMakeLists.txt

@@ -1289,6 +1289,7 @@ elseif (WTF_CPU_MIPS)

 elseif (WTF_CPU_SH4)

 elseif (WTF_CPU_X86)

 elseif (WTF_CPU_X86_64)

+elseif (WTF_CPU_RISCV64)

     if (MSVC AND ENABLE_JIT)

         add_custom_command(

             OUTPUT ${DERIVED_SOURCES_DIR}/JITStubsMSVC64.obj

diff --git a/Source/ThirdParty/brotli/dec/port.h b/Source/ThirdParty/brotli/dec/port.h

index 6b3d7352b..54f51b010 100644

--- a/Source/ThirdParty/brotli/dec/port.h

+++ b/Source/ThirdParty/brotli/dec/port.h

@@ -56,6 +56,10 @@

 #define BROTLI_TARGET_POWERPC64

 #endif

+#if defined(__riscv) && defined(__riscv_xlen) && __riscv_xlen == 64

+#define BROTLI_TARGET_RISCV64

+#endif

+

 #ifdef BROTLI_BUILD_PORTABLE

 #define BROTLI_ALIGNED_READ (!!1)

 #elif defined(BROTLI_TARGET_X86) || defined(BROTLI_TARGET_X64) || \

@@ -96,7 +100,7 @@ static BROTLI_INLINE void BrotliDump(const char* f, int l, const char* fn) {

 #elif defined(BROTLI_BUILD_32_BIT)

 #define BROTLI_64_BITS 0

 #elif defined(BROTLI_TARGET_X64) || defined(BROTLI_TARGET_ARMV8) || \

-    defined(BROTLI_TARGET_POWERPC64)

+    defined(BROTLI_TARGET_POWERPC64) || defined(BROTLI_TARGET_RISCV64)

 #define BROTLI_64_BITS 1

 #else

 #define BROTLI_64_BITS 0

diff --git a/Tools/Scripts/webkitdirs.pm b/Tools/Scripts/webkitdirs.pm

index 45b6649a9..1b32756fc 100755

--- a/Tools/Scripts/webkitdirs.pm

+++ b/Tools/Scripts/webkitdirs.pm

@@ -1264,6 +1264,11 @@ sub isARM()

     return ($Config{archname} =~ /^arm[v\-]/) || ($Config{archname} =~ /^aarch64[v\-]/);

 }

+sub isRISCV()

+{

+    return ($Config{archname} =~ /^riscv(|32|64)\-/);

+}

+

 sub isX86_64()

 {

     return (architecture() eq "x86_64") || 0;