Enable chkstk/alloca intrinsics on x86_64-unknown-uefi

Author: nicholasbishop

compiler-builtins/src/x86_64.rs

@@ -11,8 +11,7 @@ use core::intrinsics;
 intrinsics! {
     #[naked]
     #[cfg(all(
-        windows,
-        target_env = "gnu",
+        any(all(windows, target_env = "gnu"), target_os = "uefi"),
         not(feature = "no-asm")
     ))]
     pub unsafe extern "C" fn ___chkstk_ms() {
@@ -40,8 +39,7 @@ intrinsics! {
 
     #[naked]
     #[cfg(all(
-        windows,
-        target_env = "gnu",
+        any(all(windows, target_env = "gnu"), target_os = "uefi"),
         not(feature = "no-asm")
     ))]
     pub unsafe extern "C" fn __alloca() {
@@ -54,8 +52,7 @@ intrinsics! {
 
     #[naked]
     #[cfg(all(
-        windows,
-        target_env = "gnu",
+        any(all(windows, target_env = "gnu"), target_os = "uefi"),
         not(feature = "no-asm")
     ))]
     pub unsafe extern "C" fn ___chkstk() {