reflect: add support for riscv64

Based on riscv-go port.

Update #27532

Change-Id: I791924f71078fd8dfe9c2fc03a3f21a3bc673721
Reviewed-on: https://go-review.googlesource.com/c/go/+/204634
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
diff --git a/src/reflect/asm_riscv64.s b/src/reflect/asm_riscv64.s
new file mode 100644
index 0000000..f5886e5
--- /dev/null
+++ b/src/reflect/asm_riscv64.s
@@ -0,0 +1,36 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+#include "funcdata.h"
+
+// makeFuncStub is the code half of the function returned by MakeFunc.
+// See the comment on the declaration of makeFuncStub in makefunc.go
+// for more details.
+// No arg size here, runtime pulls arg map out of the func value.
+TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$32
+	NO_LOCAL_POINTERS
+	MOV	CTXT, 8(SP)
+	MOV	$argframe+0(FP), T0
+	MOV	T0, 16(SP)
+	ADD	$32, SP, T1
+	MOV	T1, 24(SP)
+	MOVB	R0, 32(SP)
+	CALL	·callReflect(SB)
+	RET
+
+// methodValueCall is the code half of the function returned by makeMethodValue.
+// See the comment on the declaration of methodValueCall in makefunc.go
+// for more details.
+// No arg size here; runtime pulls arg map out of the func value.
+TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$32
+	NO_LOCAL_POINTERS
+	MOV	CTXT, 8(SP)
+	MOV	$argframe+0(FP), T0
+	MOV	T0, 16(SP)
+	ADD	$32, SP, T1
+	MOV	T1, 24(SP)
+	MOVB	R0, 32(SP)
+	CALL	·callMethod(SB)
+	RET