Add testing for Arm64EC Windows

Author: dpaoliello

.github/workflows/main.yml

@@ -105,6 +105,15 @@ jobs:
             os: windows-11-arm
             rust: stable
             target: aarch64-pc-windows-msvc
+          - build: cross-windows-arm64ec
+            os: windows-latest
+            rust: beta
+            target: arm64ec-pc-windows-msvc
+            no_run: --no-run
+          - build: windows-arm64ec
+            os: windows-11-arm
+            rust: beta
+            target: arm64ec-pc-windows-msvc
           - build: cross-win64
             os: windows-11-arm
             rust: stable

dev-tools/cc-test/build.rs

@@ -134,6 +134,18 @@ fn main() {
             .arg("/fsrc/NMakefile")
             .env("OUT_DIR", &out)
             .env("CC_FRONTEND", cc_frontend)
+            .env(
+                "EXTRA_CFLAGS",
+                if arch == "arm64ec" { "-arm64EC" } else { "" },
+            )
+            .env(
+                "EXTRA_LIBFLAGS",
+                if arch == "arm64ec" {
+                    "-machine:arm64ec"
+                } else {
+                    ""
+                },
+            )
             .status()
             .unwrap();
         assert!(status.success());

dev-tools/cc-test/src/NMakefile

@@ -1,14 +1,14 @@
 all: $(OUT_DIR)/msvc.lib $(OUT_DIR)/msvc.exe
 
 !IF "$(CC_FRONTEND)" == "MSVC"
-EXTRA_CFLAGS=-nologo
+EXTRA_CFLAGS=$(EXTRA_CFLAGS) -nologo
 CFLAG_OUTPUT=-Fo
 !ELSE
 CFLAG_OUTPUT=-o
 !ENDIF
 
 $(OUT_DIR)/msvc.lib: $(OUT_DIR)/msvc.o
-	lib -nologo -out:$(OUT_DIR)/msvc.lib $(OUT_DIR)/msvc.o
+	lib $(EXTRA_LIBFLAGS) -nologo -out:$(OUT_DIR)/msvc.lib $(OUT_DIR)/msvc.o
 
 $(OUT_DIR)/msvc.o: src/msvc.c
 	$(CC) $(EXTRA_CFLAGS) -c $(CFLAG_OUTPUT)$@ src/msvc.c -MD

dev-tools/cc-test/src/arm64ec.asm

@@ -0,0 +1,8 @@
+    AREA |.text|, CODE, READONLY
+    GLOBAL |#asm|
+    ALIGN 4
+|#asm| PROC
+    mov w0, #7
+    ret
+    ENDP
+    END

src/lib.rs

@@ -1399,7 +1399,6 @@ impl Build {
         }
 
         let mut cmd = compiler.to_command();
-        let is_arm = matches!(target.arch, "aarch64" | "arm64ec" | "arm");
         command_add_output_file(
             &mut cmd,
             &obj,
@@ -1410,7 +1409,7 @@ impl Build {
                 clang: compiler.is_like_clang(),
                 gnu: compiler.is_like_gnu(),
                 is_asm: false,
-                is_arm,
+                is_arm: is_arm(target),
             },
         );
 
@@ -1845,7 +1844,7 @@ impl Build {
             }
             cmd
         };
-        let is_arm = matches!(target.arch, "aarch64" | "arm64ec" | "arm");
+        let is_arm = is_arm(&target);
         command_add_output_file(
             &mut cmd,
             &obj.dst,
@@ -2607,11 +2606,15 @@ impl Build {
         for directory in self.include_directories.iter() {
             cmd.arg("-I").arg(&**directory);
         }
-        if matches!(target.arch, "aarch64" | "arm64ec" | "arm") {
+        if is_arm(&target) {
             if self.get_debug() {
                 cmd.arg("-g");
             }
 
+            if target.arch == "arm64ec" {
+                cmd.args(["-machine", "ARM64EC"]);
+            }
+
             for (key, value) in self.definitions.iter() {
                 cmd.arg("-PreDefine");
                 if let Some(ref value) = *value {
@@ -4301,6 +4304,10 @@ fn map_darwin_target_from_rust_to_compiler_architecture<'a>(target: &TargetInfo<
     }
 }
 
+fn is_arm(target: &TargetInfo<'_>) -> bool {
+    matches!(target.arch, "aarch64" | "arm64ec" | "arm")
+}
+
 #[derive(Clone, Copy, PartialEq)]
 enum AsmFileExt {
     /// `.asm` files. On MSVC targets, we assume these should be passed to MASM