Auto merge of #174 - alexcrichton:less-compiler-rt, r=alexcrichton

Use the Rust implementation of udivsi3 on ARM

Although compiler-rt presumably has a more optimized implementation written in
assembly, it appears buggy for whatever reason, causing #173.

For now let's see if integration into rust-lang/rust will work with the
Rust-defined implementation!

Author: bors

build.rs

@@ -4204,7 +4204,6 @@ mod c {
                     "arm/switchu8.S",
                     "arm/sync_synchronize.S",
                     "arm/udivmodsi4.S",
-                    "arm/udivsi3.S",
                     "arm/umodsi3.S",
                 ],
             );

src/int/udiv.rs

@@ -148,9 +148,6 @@ macro_rules! udivmod_inner {
 }
 
 intrinsics! {
-    #[use_c_shim_if(all(target_arch = "arm",
-                        not(target_os = "ios"),
-                        not(thumbv6m)))]
     #[arm_aeabi_alias = __aeabi_uidiv]
     /// Returns `n / d`
     pub extern "C" fn __udivsi3(n: u32, d: u32) -> u32 {