feat: add canonicalize_nans feature

Signed-off-by: Henry Gressmann <mail@henrygressmann.de>

4 files changed, 47 insertions, 15 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e63ff2b..8c47dea 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Support for the custom memory page sizes proposal ([#22](https://github.com/explodingcamera/tinywasm/pull/22) by [@danielstuart14](https://github.com/danielstuart14))
 - Support for the `tail_call` proposal
+- Support for the `memory64` proposal
+- Groundwork for the `simd` proposal
+- New `canonicalize_nans` feature flag to enable canonicalizing NaN values in the `f32`, `f64`, and `v128` types
 
 ### Breaking Changes
 
diff --git a/Cargo.lock b/Cargo.lock
index acdc41b..f194530 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -114,18 +114,18 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "4.5.36"
+version = "4.5.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2df961d8c8a0d08aa9945718ccf584145eee3f3aa06cddbeac12933781102e04"
+checksum = "eccb054f56cbd38340b380d4a8e69ef1f02f1af43db2f0cc817a4774d80ae071"
 dependencies = [
  "clap_builder",
 ]
 
 [[package]]
 name = "clap_builder"
-version = "4.5.36"
+version = "4.5.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "132dbda40fb6753878316a489d5a1242a8ef2f0d9e47ba01c951ea8aa7d013a5"
+checksum = "efd9466fac8543255d3b1fcad4762c5e116ffe808c8a3043d4263cd4fd4862a2"
 dependencies = [
  "anstyle",
  "clap_lex",
@@ -353,15 +353,15 @@ checksum = "09edd9e8b54e49e587e4f6295a7d29c3ea94d469cb40ab8ca70b288248a81db2"
 
 [[package]]
 name = "libc"
-version = "0.2.171"
+version = "0.2.172"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c19937216e9d3aa9956d9bb8dfc0b0c8beb6058fc4f7a4dc4d850edf86a237d6"
+checksum = "d750af042f7ef4f724306de029d18836c26c1765a54a6a3f094cbd23a7267ffa"
 
 [[package]]
 name = "libm"
-version = "0.2.11"
+version = "0.2.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8355be11b20d696c8f18f6cc018c4e372165b1fa8126cef092399c9951984ffa"
+checksum = "c9627da5196e5d8ed0b0495e61e518847578da83483c37288316d9b2e03a7f72"
 
 [[package]]
 name = "log"
@@ -426,9 +426,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.94"
+version = "1.0.95"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a31971752e70b8b2686d7e46ec17fb38dad4051d94024c88df49b667caea9c84"
+checksum = "02b3e5e68a3a1a02aad3ec490a98007cbc13c37cbe84a3cd7b8e406d76e7f778"
 dependencies = [
  "unicode-ident",
 ]
diff --git a/crates/tinywasm/Cargo.toml b/crates/tinywasm/Cargo.toml
index 3281476..10a3099 100644
--- a/crates/tinywasm/Cargo.toml
+++ b/crates/tinywasm/Cargo.toml
@@ -32,12 +32,20 @@ serde_json={version="1.0"}
 serde={version="1.0", features=["derive"]}
 
 [features]
-default=["std", "parser", "logging", "archive"]
+default=["std", "parser", "logging", "archive", "canonicalize_nans"]
+
 logging=["log", "tinywasm-parser?/logging", "tinywasm-types/logging"]
 std=["tinywasm-parser?/std", "tinywasm-types/std"]
+
+# support for parsing WebAssembly
 parser=["dep:tinywasm-parser"]
+
+# support for "archiving" tinywasm bytecode
 archive=["tinywasm-types/archive"]
 
+# canonicalize all NaN values to a single representation
+canonicalize_nans=[]
+
 # enable simd support (unstable / unfinished)
 __simd=[]
 
diff --git a/crates/tinywasm/src/interpreter/num_helpers.rs b/crates/tinywasm/src/interpreter/num_helpers.rs
index 678c32e..7e8a461 100644
--- a/crates/tinywasm/src/interpreter/num_helpers.rs
+++ b/crates/tinywasm/src/interpreter/num_helpers.rs
@@ -72,9 +72,12 @@ macro_rules! impl_wasm_float_ops {
     ($($t:ty)*) => ($(
         impl TinywasmFloatExt for $t {
             // https://webassembly.github.io/spec/core/exec/numerics.html#op-fnearest
+            #[inline]
             fn tw_nearest(self) -> Self {
                 match self {
-                    // x if x.is_nan() => x, // preserve NaN
+                    #[cfg(not(feature = "canonicalize_nans"))]
+                    x if x.is_nan() => x, // preserve NaN
+                    #[cfg(feature = "canonicalize_nans")]
                     x if x.is_nan() => Self::NAN, // Do not preserve NaN
                     x if x.is_infinite() || x == 0.0 => x, // preserve infinities and zeros
                     x if (0.0..=0.5).contains(&x) => 0.0,
@@ -100,7 +103,9 @@ macro_rules! impl_wasm_float_ops {
                     Some(core::cmp::Ordering::Less) => self,
                     Some(core::cmp::Ordering::Greater) => other,
                     Some(core::cmp::Ordering::Equal) => if self.is_sign_negative() && other.is_sign_positive() { self } else { other },
-                    // None => self + other, // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
+                    #[cfg(not(feature = "canonicalize_nans"))]
+                    None => self + other, // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
+                    #[cfg(feature = "canonicalize_nans")]
                     None => Self::NAN, // Do not preserve NaN
                 }
             }
@@ -113,7 +118,9 @@ macro_rules! impl_wasm_float_ops {
                     Some(core::cmp::Ordering::Greater) => self,
                     Some(core::cmp::Ordering::Less) => other,
                     Some(core::cmp::Ordering::Equal) => if self.is_sign_negative() && other.is_sign_positive() { other } else { self },
-                    // None => self + other, // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
+                    #[cfg(not(feature = "canonicalize_nans"))]
+                    None => self + other, // At least one input is NaN. Use `+` to perform NaN propagation and quieting.
+                    #[cfg(feature = "canonicalize_nans")]
                     None => Self::NAN, // Do not preserve NaN
                 }
             }
@@ -184,8 +191,15 @@ macro_rules! impl_checked_wrapping_rem {
 
 impl_checked_wrapping_rem! { i32 i64 u32 u64 }
 
-#[cfg(feature = "__simd")]
+#[cfg(all(feature = "__simd", not(feature = "canonicalize_nans")))]
+#[inline]
+pub(crate) fn canonicalize_f32x4(x: core::simd::f32x4) -> core::simd::f32x4 {
+    x // No need to do anything, as we are not replacing NaNs
+}
+
+#[cfg(all(feature = "__simd", feature = "canonicalize_nans"))]
 /// replace all NaNs in a f32x4 with f32::NAN
+#[inline]
 pub(crate) fn canonicalize_f32x4(x: core::simd::f32x4) -> core::simd::f32x4 {
     use core::simd::{Simd, num::SimdFloat};
     let nan = Simd::splat(f32::NAN);
@@ -193,8 +207,15 @@ pub(crate) fn canonicalize_f32x4(x: core::simd::f32x4) -> core::simd::f32x4 {
     mask.select(nan, x)
 }
 
+#[cfg(all(feature = "__simd", not(feature = "canonicalize_nans")))]
+#[inline]
+pub(crate) fn canonicalize_f64x2(x: core::simd::f64x2) -> core::simd::f64x2 {
+    x // No need to do anything, as we are not replacing NaNs
+}
+
 #[cfg(feature = "__simd")]
 /// replace all NaNs in a f64x2 with f64::NAN
+#[inline]
 pub(crate) fn canonicalize_f64x2(x: core::simd::f64x2) -> core::simd::f64x2 {
     use core::simd::{Simd, num::SimdFloat};
     let nan = Simd::splat(f64::NAN);