[PowerPC] Add readflm/setflm intrinsics to Clang

Commit dbcfbffc adds ppc.readflm and ppc.setflm intrinsics to read or
write FPSCR register. This patch adds them to Clang.

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D85874

clang/include/clang/Basic/BuiltinsPPC.def

@@ -556,6 +556,12 @@ BUILTIN(__builtin_pack_vector_int128, "V1LLLiULLiULLi", "")
 // Set the floating point rounding mode
 BUILTIN(__builtin_setrnd, "di", "")
 
+// Get content from current FPSCR
+BUILTIN(__builtin_readflm, "d", "")
+
+// Set content of FPSCR, and return its content before update
+BUILTIN(__builtin_setflm, "dd", "")
+
 // Cache built-ins
 BUILTIN(__builtin_dcbf, "vvC*", "")
 

clang/test/CodeGen/builtins-ppc.c

@@ -27,3 +27,12 @@ void test_builtin_ppc_setrnd() {
   // CHECK: call double @llvm.ppc.setrnd(i32 %2)
   res = __builtin_setrnd(x);
 }
+
+void test_builtin_ppc_flm() {
+  volatile double res;
+  // CHECK: call double @llvm.ppc.readflm()
+  res = __builtin_readflm();
+
+  // CHECK: call double @llvm.ppc.setflm(double %1)
+  res = __builtin_setflm(res);
+}

llvm/include/llvm/IR/IntrinsicsPowerPC.td

@@ -48,9 +48,11 @@ let TargetPrefix = "ppc" in {  // All intrinsics start with "llvm.ppc.".
   def int_ppc_eieio : Intrinsic<[],[],[]>;
 
   // Get content from current FPSCR register
-  def int_ppc_readflm : Intrinsic<[llvm_double_ty], [], [IntrNoMem]>;
+  def int_ppc_readflm : GCCBuiltin<"__builtin_readflm">,
+                        Intrinsic<[llvm_double_ty], [], [IntrNoMem]>;
   // Set FPSCR register, and return previous content
-  def int_ppc_setflm : Intrinsic<[llvm_double_ty], [llvm_double_ty], []>;
+  def int_ppc_setflm : GCCBuiltin<"__builtin_setflm">,
+                       Intrinsic<[llvm_double_ty], [llvm_double_ty], []>;
 
   // Intrinsics for [double]word extended forms of divide instructions
   def int_ppc_divwe : GCCBuiltin<"__builtin_divwe">,