From 36f93dbd791338f85cd7b9e7af69dbffadeff858 Mon Sep 17 00:00:00 2001
From: Jorge Aparicio <jorge@japaric.io>
Date: Thu, 12 Jul 2018 20:40:30 -0500
Subject: [PATCH 1/3] expose math symbol on wasm32-unknown-unknown

---
 .gitmodules |  3 +++
 .travis.yml |  3 +++
 libm        |  1 +
 src/lib.rs  |  3 +++
 src/math.rs | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 61 insertions(+)
 create mode 160000 libm
 create mode 100644 src/math.rs

diff --git a/.gitmodules b/.gitmodules
index 3ff1154..7162b2c 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,6 @@
 [submodule "compiler-rt"]
 	path = compiler-rt
 	url = https://github.com/rust-lang/compiler-rt
+[submodule "libm"]
+	path = libm
+	url = https://github.com/japaric/libm
diff --git a/.travis.yml b/.travis.yml
index efd0b17..7b7ed7e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -25,6 +25,9 @@ matrix:
     - env: TARGET=thumbv7em-linux-eabi
     - env: TARGET=thumbv7em-linux-eabihf
     - env: TARGET=thumbv7m-linux-eabi
+    - env: TARGET=wasm32-unknown-unknown
+      install: rustup target add $TARGET
+      script: cargo build --target $TARGET
     - env: TARGET=x86_64-apple-darwin
       os: osx
     - env: TARGET=x86_64-unknown-linux-gnu
diff --git a/libm b/libm
new file mode 160000
index 0000000..d65f60f
--- /dev/null
+++ b/libm
@@ -0,0 +1 @@
+Subproject commit d65f60f24289ba212f5d47792f7236857efb2339
diff --git a/src/lib.rs b/src/lib.rs
index 619b6ac..3e665a8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -48,6 +48,9 @@ pub mod int;
 pub mod float;
 
 pub mod mem;
+// only for the wasm32-unknown-unknown target
+#[cfg(all(target_arch = "wasm32", target_os = "unknown"))]
+pub mod math;
 
 #[cfg(target_arch = "arm")]
 pub mod arm;
diff --git a/src/math.rs b/src/math.rs
new file mode 100644
index 0000000..f9ee36f
--- /dev/null
+++ b/src/math.rs
@@ -0,0 +1,51 @@
+#[allow(dead_code)]
+#[path = "../../libm/src/math/mod.rs"]
+mod libm;
+
+macro_rules! no_mangle {
+    ($(fn $fun:ident($($iid:ident : $ity:ty),+) -> $oty:ty;)+) => {
+        $(
+            #[no_mangle]
+            pub fn $fun($($iid: $ity),+) -> $oty {
+                self::libm::$fun($($iid),+)
+            }
+        )+
+    }
+}
+
+no_mangle! {
+    fn acos(x: f64) -> f64;
+    fn asin(x: f64) -> f64;
+    fn atan(x: f64) -> f64;
+    fn atan2(x: f64, y: f64) -> f64;
+    fn cbrt(x: f64) -> f64;
+    fn cosh(x: f64) -> f64;
+    fn expm1(x: f64) -> f64;
+    fn hypot(x: f64, y: f64) -> f64;
+    fn log1p(x: f64) -> f64;
+    fn sinh(x: f64) -> f64;
+    fn tan(x: f64) -> f64;
+    fn tanh(x: f64) -> f64;
+    fn cos(x: f64) -> f64;
+    fn cosf(x: f32) -> f32;
+    fn exp(x: f64) -> f64;
+    fn expf(x: f32) -> f32;
+    fn log2(x: f64) -> f64;
+    fn log2f(x: f32) -> f32;
+    fn log10(x: f64) -> f64;
+    fn log10f(x: f32) -> f32;
+    fn log(x: f64) -> f64;
+    fn logf(x: f32) -> f32;
+    fn round(x: f64) -> f64;
+    fn roundf(x: f32) -> f32;
+    fn sin(x: f64) -> f64;
+    fn sinf(x: f32) -> f32;
+    fn pow(x: f64, y: f64) -> f64;
+    fn powf(x: f32, y: f32) -> f32;
+    fn exp2(x: f64) -> f64;
+    fn exp2f(x: f32) -> f32;
+    fn fmod(x: f64, y: f64) -> f64;
+    fn fmodf(x: f32, y: f32) -> f32;
+    fn fma(x: f64, y: f64, z: f64) -> f64;
+    fn fmaf(x: f32, y: f32, z: f32) -> f32;
+}

From cc78ff665ddb2ed23472e7ac336c3fe29c9097b7 Mon Sep 17 00:00:00 2001
From: Jorge Aparicio <jorge@japaric.io>
Date: Wed, 18 Jul 2018 11:36:24 -0500
Subject: [PATCH 2/3] fix path

---
 src/math.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/math.rs b/src/math.rs
index f9ee36f..76bb726 100644
--- a/src/math.rs
+++ b/src/math.rs
@@ -1,5 +1,5 @@
 #[allow(dead_code)]
-#[path = "../../libm/src/math/mod.rs"]
+#[path = "../libm/src/math/mod.rs"]
 mod libm;
 
 macro_rules! no_mangle {

From d73ccba9886acc132a1d7e9565509c98fdd7c39b Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Wed, 18 Jul 2018 10:04:33 -0700
Subject: [PATCH 3/3] Use `intrinsics!` macro for math intrinsics

Make sure they respect the `mangled-names` feature as well as have the `"C"`
ABI.
---
 src/math.rs | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/math.rs b/src/math.rs
index 76bb726..f1eaaa5 100644
--- a/src/math.rs
+++ b/src/math.rs
@@ -4,12 +4,13 @@ mod libm;
 
 macro_rules! no_mangle {
     ($(fn $fun:ident($($iid:ident : $ity:ty),+) -> $oty:ty;)+) => {
-        $(
-            #[no_mangle]
-            pub fn $fun($($iid: $ity),+) -> $oty {
-                self::libm::$fun($($iid),+)
-            }
-        )+
+        intrinsics! {
+            $(
+                pub extern "C" fn $fun($($iid: $ity),+) -> $oty {
+                    self::libm::$fun($($iid),+)
+                }
+            )+
+        }
     }
 }