Force the use of sysv64 calling convention in x86_64 disassembly tests (rust-lang#1187)

This ensures that results are consistent across windows/linux tests.

Author: Amanieu

crates/assert-instr-macro/src/lib.rs

@@ -114,7 +114,12 @@ pub fn assert_instr(
     // Use an ABI on Windows that passes SIMD values in registers, like what
     // happens on Unix (I think?) by default.
     let abi = if cfg!(windows) {
-        syn::LitStr::new("vectorcall", proc_macro2::Span::call_site())
+        let target = std::env::var("TARGET").unwrap();
+        if target.contains("x86_64") {
+            syn::LitStr::new("sysv64", proc_macro2::Span::call_site())
+        } else {
+            syn::LitStr::new("vectorcall", proc_macro2::Span::call_site())
+        }
     } else {
         syn::LitStr::new("C", proc_macro2::Span::call_site())
     };

crates/core_arch/src/x86/sse2.rs

@@ -2642,14 +2642,7 @@ pub unsafe fn _mm_loadu_pd(mem_addr: *const f64) -> __m128d {
 /// [Intel's documentation](https://software.intel.com/sites/landingpage/IntrinsicsGuide/#text=_mm_shuffle_pd)
 #[inline]
 #[target_feature(enable = "sse2")]
-#[cfg_attr(
-    all(test, any(not(target_os = "windows"), target_arch = "x86")),
-    cfg_attr(test, assert_instr(shufps, MASK = 2)) // FIXME shufpd expected
-)]
-#[cfg_attr(
-    all(test, all(target_os = "windows", target_arch = "x86_64")),
-    cfg_attr(test, assert_instr(shufpd, MASK = 1))
-)]
+#[cfg_attr(test, assert_instr(shufps, MASK = 2))]
 #[rustc_legacy_const_generics(2)]
 #[stable(feature = "simd_x86", since = "1.27.0")]
 pub unsafe fn _mm_shuffle_pd<const MASK: i32>(a: __m128d, b: __m128d) -> __m128d {
@@ -2664,14 +2657,7 @@ pub unsafe fn _mm_shuffle_pd<const MASK: i32>(a: __m128d, b: __m128d) -> __m128d
 /// [Intel's documentation](https://software.intel.com/sites/landingpage/IntrinsicsGuide/#text=_mm_move_sd)
 #[inline]
 #[target_feature(enable = "sse2")]
-#[cfg_attr(
-    all(test, any(not(target_os = "windows"), target_arch = "x86")),
-    assert_instr(movsd)
-)]
-#[cfg_attr(
-    all(test, all(target_os = "windows", target_arch = "x86_64")),
-    assert_instr(movlps)
-)]
+#[cfg_attr(test, assert_instr(movsd))]
 #[stable(feature = "simd_x86", since = "1.27.0")]
 pub unsafe fn _mm_move_sd(a: __m128d, b: __m128d) -> __m128d {
     _mm_setr_pd(simd_extract(b, 0), simd_extract(a, 1))