Auto merge of rust-lang#116078 - eduardosm:closure-inherit-target-feature, r=Mark-Simulacrum

Add assembly test to make sure that inlining works as expected when closures inherit target features

Closes rust-lang#108338 (the added test proves that it is working correctly)

Author: bors

tests/assembly/closure-inherit-target-feature.rs

@@ -0,0 +1,58 @@
+// only-x86_64
+// assembly-output: emit-asm
+// make sure the feature is not enabled at compile-time
+// compile-flags: -C target-feature=-sse4.1 -C llvm-args=-x86-asm-syntax=intel
+
+#![feature(target_feature_11)]
+#![crate_type = "rlib"]
+
+use std::arch::x86_64::{__m128, _mm_blend_ps};
+
+#[no_mangle]
+pub unsafe fn sse41_blend_nofeature(x: __m128, y: __m128) -> __m128 {
+    let f = {
+        // check that _mm_blend_ps is not being inlined into the closure
+        // CHECK-LABEL: {{sse41_blend_nofeature.*closure.*:}}
+        // CHECK-NOT: blendps
+        // CHECK: {{call .*_mm_blend_ps.*}}
+        // CHECK-NOT: blendps
+        // CHECK: ret
+        #[inline(never)] |x, y| _mm_blend_ps(x, y, 0b0101)
+    };
+    f(x, y)
+}
+
+#[target_feature(enable = "sse4.1")]
+pub fn sse41_blend_noinline(x: __m128, y: __m128) -> __m128 {
+    let f = {
+        // check that _mm_blend_ps is being inlined into the closure
+        // CHECK-LABEL: {{sse41_blend_noinline.*closure.*:}}
+        // CHECK-NOT: _mm_blend_ps
+        // CHECK: blendps
+        // CHECK-NOT: _mm_blend_ps
+        // CHECK: ret
+        #[inline(never)] |x, y| unsafe {
+            _mm_blend_ps(x, y, 0b0101)
+        }
+    };
+    f(x, y)
+}
+
+#[no_mangle]
+#[target_feature(enable = "sse4.1")]
+pub fn sse41_blend_doinline(x: __m128, y: __m128) -> __m128 {
+    // check that the closure and _mm_blend_ps are being inlined into the function
+    // CHECK-LABEL: sse41_blend_doinline:
+    // CHECK-NOT: {{sse41_blend_doinline.*closure.*}}
+    // CHECK-NOT: _mm_blend_ps
+    // CHECK: blendps
+    // CHECK-NOT: {{sse41_blend_doinline.*closure.*}}
+    // CHECK-NOT: _mm_blend_ps
+    // CHECK: ret
+    let f = {
+        #[inline] |x, y| unsafe {
+            _mm_blend_ps(x, y, 0b0101)
+        }
+    };
+    f(x, y)
+}