riscv64: fenv implementation.

Signed-off-by: Mao Han <han_mao@linux.alibaba.com>
Signed-off-by: Xia Lifang <lifang_xia@linux.alibaba.com>
Signed-off-by: Chen Guoyin <chenguoyin.cgy@linux.alibaba.com>
Signed-off-by: Wang Chen <wangchen20@iscas.ac.cn>
Signed-off-by: Lu Xufan <luxufan@iscas.ac.cn>
Test: treehugger
Change-Id: I0f0227cd4cb5e78aba1a749f8d8fce296a024dfb
diff --git a/libm/Android.bp b/libm/Android.bp
index 641956c..effd7e9 100644
--- a/libm/Android.bp
+++ b/libm/Android.bp
@@ -344,6 +344,13 @@
             version_script: ":libm.arm64.map",
         },
 
+        riscv64: {
+            srcs: [
+                "riscv64/fenv.c",
+            ],
+            version_script: ":libm.riscv64.map",
+        },
+
         x86: {
             srcs: [
                 "i387/fenv.c",
@@ -573,6 +580,14 @@
 }
 
 genrule {
+    name: "libm.riscv64.map",
+    out: ["libm.riscv64.map"],
+    srcs: ["libm.map.txt"],
+    tools: ["generate-version-script"],
+    cmd: "$(location generate-version-script) riscv64 $(in) $(out)",
+}
+
+genrule {
     name: "libm.x86.map",
     out: ["libm.x86.map"],
     srcs: ["libm.map.txt"],