ARM: Fix an issue with clang generating wrong code.

Clang generated executables would enter the if condition when it wasn't
supposted to, resulting in the wrong simulated behavior.
Implementing the operation this way is a bit faster anyway.

diff --git a/src/arch/arm/insts/vfp.cc b/src/arch/arm/insts/vfp.cc
index f689204d9c79b5de3d49a397739b2d34e0371d9a..6e15282f81c5164ea08753e42e9e4fd1e33045a5 100644 (file)
--- a/src/arch/arm/insts/vfp.cc
+++ b/src/arch/arm/insts/vfp.cc
@@ -993,9 +993,8 @@ FpOp::binaryOp(FPSCR &fpscr, fpType op1, fpType op2,
     fpType dest = func(op1, op2);
     __asm__ __volatile__ ("" : "=m" (dest) : "m" (dest));
 
-    int fpClass = std::fpclassify(dest);
     // Get NAN behavior right. This varies between x86 and ARM.
-    if (fpClass == FP_NAN) {
+    if (std::isnan(dest)) {
         const bool single = (sizeof(fpType) == sizeof(float));
         const uint64_t qnan =
             single ? 0x7fc00000 : ULL(0x7ff8000000000000);
@@ -1065,9 +1064,8 @@ FpOp::unaryOp(FPSCR &fpscr, fpType op1, fpType (*func)(fpType),
     fpType dest = func(op1);
     __asm__ __volatile__ ("" : "=m" (dest) : "m" (dest));
 
-    int fpClass = std::fpclassify(dest);
     // Get NAN behavior right. This varies between x86 and ARM.
-    if (fpClass == FP_NAN) {
+    if (std::isnan(dest)) {
         const bool single = (sizeof(fpType) == sizeof(float));
         const uint64_t qnan =
             single ? 0x7fc00000 : ULL(0x7ff8000000000000);