Support arithmetic/canonical NaN; update testsuite (#368)

Positive NaN (+nan) is defined as being a NaN value where the sign bit
is clear, the exponent is all ones, and the tag has only the "quiet" bit
set. The quiet bit is the most-significant bit of the tag. For example,
for a 32-bit float, +nan is 0x7cf00000.

"Canonical NaN" is either +nan or -nan, where -nan is +nan with the sign
bit set.

"Arithmetic NaN" is defined as any other quiet NaN (i.e. the quiet bit
must be set, but any other bit can be either 0 or 1.)

This change doesn't update the interpreter because it is only a
loosening of the previous NaN behavior.

1 files changed, 4 insertions, 2 deletions

diff --git a/src/interpreter.h b/src/interpreter.h
index 94125005..28b15b33 100644
--- a/src/interpreter.h
+++ b/src/interpreter.h
@@ -361,8 +361,10 @@ struct InterpreterThreadOptions {
   uint32_t pc;
 };
 
-bool is_nan_f32(uint32_t f32_bits);
-bool is_nan_f64(uint64_t f64_bits);
+bool is_canonical_nan_f32(uint32_t f32_bits);
+bool is_canonical_nan_f64(uint64_t f64_bits);
+bool is_arithmetic_nan_f32(uint32_t f32_bits);
+bool is_arithmetic_nan_f64(uint64_t f64_bits);
 bool func_signatures_are_equal(InterpreterEnvironment* env,
                                uint32_t sig_index_0,
                                uint32_t sig_index_1);