Merge pull request #251 from riscv-rust/master

Implement __mulsi3.
master
Alex Crichton 2018-08-03 14:09:12 -05:00 committed by GitHub
commit 5a7b58ffd7
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2 changed files with 20 additions and 0 deletions

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@ -58,6 +58,9 @@ pub mod arm;
#[cfg(all(kernel_user_helpers, target_os = "linux", target_arch = "arm"))]
pub mod arm_linux;
#[cfg(any(target_arch = "riscv32"))]
pub mod riscv32;
#[cfg(target_arch = "x86")]
pub mod x86;

17
src/riscv32.rs Normal file
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@ -0,0 +1,17 @@
intrinsics! {
// Implementation from gcc
// https://raw.githubusercontent.com/gcc-mirror/gcc/master/libgcc/config/epiphany/mulsi3.c
pub extern "C" fn __mulsi3(mut a: u32, mut b: u32) -> u32 {
let mut r: usize = 0;
while a > 0 {
if a & 1 > 0 {
r += b;
}
a >>= 1;
b <<= 1;
}
r
}
}