Add assembly tests for -Zreg-struct-return

Author: winstonallo

tests/assembly-llvm/reg-struct-return.rs

@@ -0,0 +1,61 @@
+// Test the reg-struct-return ABI.
+//@ add-core-stubs
+//@ assembly-output: emit-asm
+//@ compile-flags: -O --target=i686-unknown-linux-gnu -Crelocation-model=static
+//@ revisions: WITH WITHOUT
+//@[WITH] compile-flags: -Zreg-struct-return
+//@ needs-llvm-components: x86
+
+#![feature(no_core)]
+#![no_std]
+#![no_core]
+#![crate_type = "lib"]
+
+extern crate minicore;
+use minicore::*;
+
+struct div_t {
+    quot: i32,
+    rem: i32,
+}
+
+unsafe extern "C" {
+    fn div(numerator: i32, denominator: i32) -> div_t;
+}
+
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn direct_construction(numerator: i32, denominator: i32) -> div_t {
+    // WITH-LABEL: direct_construction
+    // WITH: movl $42, %eax
+    // WITH: movl $42, %edx
+    // WITH: retl
+
+    // WITHOUT-LABEL: direct_construction
+    // WITHOUT: movl 4(%esp), %eax
+    // WITHOUT: movl $42, (%eax)
+    // WITHOUT: movl $42, 4(%eax)
+    // WITHOUT: retl $4
+    div_t { quot: 42, rem: 42 }
+}
+
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn builtin_call(numerator: i32, denominator: i32) -> div_t {
+    // WITH-LABEL: builtin_call
+    // WITH: jmp div
+
+    // WITHOUT-LABEL: builtin_call
+    // WITHOUT: pushl %esi
+    // WITHOUT: subl $8, %esp
+    // WITHOUT: movl 16(%esp), %esi
+    // WITHOUT: subl $4, %esp
+    // WITHOUT: pushl 28(%esp)
+    // WITHOUT: pushl 28(%esp)
+    // WITHOUT: pushl %esi
+    // WITHOUT: calll div
+    // WITHOUT: addl $12, %esp
+    // WITHOUT: movl %esi, %eax
+    // WITHOUT: addl $8, %esp
+    // WITHOUT: popl %esi
+    // WITHOUT: retl $4
+    div(numerator, denominator)
+}