Add 'compiler/rustc_codegen_gcc/' from commit 'afae271d5d'

git-subtree-dir: compiler/rustc_codegen_gcc
git-subtree-mainline: ae90dcf020
git-subtree-split: afae271d5d

compiler/rustc_codegen_gcc/example/mod_bench.rs

@@ -0,0 +1,37 @@
+#![feature(start, box_syntax, core_intrinsics, lang_items)]
+#![no_std]
+
+#[link(name = "c")]
+extern {}
+
+#[panic_handler]
+fn panic_handler(_: &core::panic::PanicInfo) -> ! {
+    unsafe {
+        core::intrinsics::abort();
+    }
+}
+
+#[lang="eh_personality"]
+fn eh_personality(){}
+
+// Required for rustc_codegen_llvm
+#[no_mangle]
+unsafe extern "C" fn _Unwind_Resume() {
+    core::intrinsics::unreachable();
+}
+
+#[start]
+fn main(_argc: isize, _argv: *const *const u8) -> isize {
+    for i in 2..100_000_000 {
+        black_box((i + 1) % i);
+    }
+
+    0
+}
+
+#[inline(never)]
+fn black_box(i: u32) {
+    if i != 1 {
+        unsafe { core::intrinsics::abort(); }
+    }
+}