r218488 - CGBuiltin: Use frem instruction rather than libcall to implement fmod

[Jan Vesely]

Author: jvesely
Date: Thu Sep 25 20:19:41 2014
New Revision: 218488

URL: http://llvm.org/viewvc/llvm-project?rev=218488&view=rev
Log:
CGBuiltin: Use frem instruction rather than libcall to implement fmod

AFAICT the semantics of frem match libm's fmod.

Signed-off-by: Jan Vesely <jan.vesely at rutgers.edu>
Reviewed-by: Tom Stellard <tom at stellard.net>

Modified:
    cfe/trunk/lib/CodeGen/CGBuiltin.cpp
    cfe/trunk/test/CodeGen/builtins.c

Modified: cfe/trunk/lib/CodeGen/CGBuiltin.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGBuiltin.cpp?rev=218488&r1=218487&r2=218488&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGBuiltin.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGBuiltin.cpp Thu Sep 25 20:19:41 2014
@@ -241,6 +241,14 @@ RValue CodeGenFunction::EmitBuiltinExpr(
 
     return RValue::get(Result);
   }
+  case Builtin::BI__builtin_fmod:
+  case Builtin::BI__builtin_fmodf:
+  case Builtin::BI__builtin_fmodl: {
+    Value *Arg1 = EmitScalarExpr(E->getArg(0));
+    Value *Arg2 = EmitScalarExpr(E->getArg(1));
+    Value *Result = Builder.CreateFRem(Arg1, Arg2, "fmod");
+    return RValue::get(Result);
+  }
 
   case Builtin::BI__builtin_conj:
   case Builtin::BI__builtin_conjf:

Modified: cfe/trunk/test/CodeGen/builtins.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/builtins.c?rev=218488&r1=218487&r2=218488&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/builtins.c (original)
+++ cfe/trunk/test/CodeGen/builtins.c Thu Sep 25 20:19:41 2014
@@ -197,6 +197,22 @@ void test_float_builtins(float F, double
   // CHECK: and i1
 }
 
+// CHECK-LABEL: define void @test_float_builtin_ops
+void test_float_builtin_ops(float F, double D, long double LD) {
+  volatile float resf;
+  volatile double resd;
+  volatile long double resld;
+
+  resf = __builtin_fmodf(F,F);
+  // CHECK: frem float
+
+  resd = __builtin_fmod(D,D);
+  // CHECK: frem double
+
+  resld = __builtin_fmodl(LD,LD);
+  // CHECK: frem x86_fp80
+}
+
 // CHECK-LABEL: define void @test_builtin_longjmp
 void test_builtin_longjmp(void **buffer) {
   // CHECK: [[BITCAST:%.*]] = bitcast