Ban non-array SIMD

rust-lang · Aug 22, 2024 · f48908d · f48908d
1 parent a32d4a0
commit f48908d
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Showing 85 changed files with 659 additions and 811 deletions.
diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs
@@ -1063,20 +1063,29 @@ pub fn check_simd(tcx: TyCtxt<'_>, sp: Span, def_id: LocalDefId) {
             struct_span_code_err!(tcx.dcx(), sp, E0075, "SIMD vector cannot be empty").emit();
             return;
         }
-        let e = fields[FieldIdx::ZERO].ty(tcx, args);
-        if !fields.iter().all(|f| f.ty(tcx, args) == e) {
-            struct_span_code_err!(tcx.dcx(), sp, E0076, "SIMD vector should be homogeneous")
-                .with_span_label(sp, "SIMD elements must have the same type")
+
+        let array_field = &fields[FieldIdx::ZERO];
+        let array_ty = array_field.ty(tcx, args);
+        let ty::Array(element_ty, len_const) = array_ty.kind() else {
+            struct_span_code_err!(
+                tcx.dcx(),
+                sp,
+                E0076,
+                "SIMD vector's only field must be an array"
+            )
+            .with_span_label(tcx.def_span(array_field.did), "not an array")
+            .emit();
+            return;
+        };
+
+        if let Some(second_field) = fields.get(FieldIdx::from_u32(1)) {
+            struct_span_code_err!(tcx.dcx(), sp, E0075, "SIMD vector cannot have multiple fields")
+                .with_span_label(tcx.def_span(second_field.did), "excess field")
                 .emit();
             return;
         }
 
-        let len = if let ty::Array(_ty, c) = e.kind() {
-            c.try_eval_target_usize(tcx, tcx.param_env(def.did()))
-        } else {
-            Some(fields.len() as u64)
-        };
-        if let Some(len) = len {
+        if let Some(len) = len_const.try_eval_target_usize(tcx, tcx.param_env(def.did())) {
             if len == 0 {
                 struct_span_code_err!(tcx.dcx(), sp, E0075, "SIMD vector cannot be empty").emit();
                 return;
@@ -1096,16 +1105,9 @@ pub fn check_simd(tcx: TyCtxt<'_>, sp: Span, def_id: LocalDefId) {
         // These are scalar types which directly match a "machine" type
         // Yes: Integers, floats, "thin" pointers
         // No: char, "fat" pointers, compound types
-        match e.kind() {
-            ty::Param(_) => (), // pass struct<T>(T, T, T, T) through, let monomorphization catch errors
-            ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::RawPtr(_, _) => (), // struct(u8, u8, u8, u8) is ok
-            ty::Array(t, _) if matches!(t.kind(), ty::Param(_)) => (), // pass struct<T>([T; N]) through, let monomorphization catch errors
-            ty::Array(t, _clen)
-                if matches!(
-                    t.kind(),
-                    ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::RawPtr(_, _)
-                ) =>
-            { /* struct([f32; 4]) is ok */ }
+        match element_ty.kind() {
+            ty::Param(_) => (), // pass struct<T>([T; 4]) through, let monomorphization catch errors
+            ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::RawPtr(_, _) => (), // struct([u8; 4]) is ok
             _ => {
                 struct_span_code_err!(
                     tcx.dcx(),

diff --git a/compiler/rustc_middle/src/ty/sty.rs b/compiler/rustc_middle/src/ty/sty.rs
@@ -1091,29 +1091,21 @@ impl<'tcx> Ty<'tcx> {
     }
 
     pub fn simd_size_and_type(self, tcx: TyCtxt<'tcx>) -> (u64, Ty<'tcx>) {
-        match self.kind() {
-            Adt(def, args) => {
-                assert!(def.repr().simd(), "`simd_size_and_type` called on non-SIMD type");
-                let variant = def.non_enum_variant();
-                let f0_ty = variant.fields[FieldIdx::ZERO].ty(tcx, args);
-
-                match f0_ty.kind() {
-                    // If the first field is an array, we assume it is the only field and its
-                    // elements are the SIMD components.
-                    Array(f0_elem_ty, f0_len) => {
-                        // FIXME(repr_simd): https://github.com/rust-lang/rust/pull/78863#discussion_r522784112
-                        // The way we evaluate the `N` in `[T; N]` here only works since we use
-                        // `simd_size_and_type` post-monomorphization. It will probably start to ICE
-                        // if we use it in generic code. See the `simd-array-trait` ui test.
-                        (f0_len.eval_target_usize(tcx, ParamEnv::empty()), *f0_elem_ty)
-                    }
-                    // Otherwise, the fields of this Adt are the SIMD components (and we assume they
-                    // all have the same type).
-                    _ => (variant.fields.len() as u64, f0_ty),
-                }
-            }
-            _ => bug!("`simd_size_and_type` called on invalid type"),
-        }
+        let Adt(def, args) = self.kind() else {
+            bug!("`simd_size_and_type` called on invalid type")
+        };
+        assert!(def.repr().simd(), "`simd_size_and_type` called on non-SIMD type");
+        let variant = def.non_enum_variant();
+        assert_eq!(variant.fields.len(), 1);
+        let field_ty = variant.fields[FieldIdx::ZERO].ty(tcx, args);
+        let Array(f0_elem_ty, f0_len) = field_ty.kind() else {
+            bug!("Simd type has non-array field type {field_ty:?}")
+        };
+        // FIXME(repr_simd): https://github.com/rust-lang/rust/pull/78863#discussion_r522784112
+        // The way we evaluate the `N` in `[T; N]` here only works since we use
+        // `simd_size_and_type` post-monomorphization. It will probably start to ICE
+        // if we use it in generic code. See the `simd-array-trait` ui test.
+        (f0_len.eval_target_usize(tcx, ParamEnv::empty()), *f0_elem_ty)
     }
 
     #[inline]

diff --git a/tests/codegen/align-byval-vector.rs b/tests/codegen/align-byval-vector.rs
@@ -21,7 +21,7 @@ trait Freeze {}
 trait Copy {}
 
 #[repr(simd)]
-pub struct i32x4(i32, i32, i32, i32);
+pub struct i32x4([i32; 4]);
 
 #[repr(C)]
 pub struct Foo {
@@ -47,12 +47,12 @@ extern "C" {
 }
 
 pub fn main() {
-    unsafe { f(Foo { a: i32x4(1, 2, 3, 4), b: 0 }) }
+    unsafe { f(Foo { a: i32x4([1, 2, 3, 4]), b: 0 }) }
 
     unsafe {
         g(DoubleFoo {
-            one: Foo { a: i32x4(1, 2, 3, 4), b: 0 },
-            two: Foo { a: i32x4(1, 2, 3, 4), b: 0 },
+            one: Foo { a: i32x4([1, 2, 3, 4]), b: 0 },
+            two: Foo { a: i32x4([1, 2, 3, 4]), b: 0 },
         })
     }
 }
diff --git a/tests/codegen/const-vector.rs b/tests/codegen/const-vector.rs
@@ -13,19 +13,11 @@
 // Setting up structs that can be used as const vectors
 #[repr(simd)]
 #[derive(Clone)]
-pub struct i8x2(i8, i8);
+pub struct i8x2([i8; 2]);
 
 #[repr(simd)]
 #[derive(Clone)]
-pub struct i8x2_arr([i8; 2]);
-
-#[repr(simd)]
-#[derive(Clone)]
-pub struct f32x2(f32, f32);
-
-#[repr(simd)]
-#[derive(Clone)]
-pub struct f32x2_arr([f32; 2]);
+pub struct f32x2([f32; 2]);
 
 #[repr(simd, packed)]
 #[derive(Copy, Clone)]
@@ -35,42 +27,34 @@ pub struct Simd<T, const N: usize>([T; N]);
 // that they are called with a const vector
 
 extern "unadjusted" {
-    #[no_mangle]
     fn test_i8x2(a: i8x2);
 }
 
 extern "unadjusted" {
-    #[no_mangle]
     fn test_i8x2_two_args(a: i8x2, b: i8x2);
 }
 
 extern "unadjusted" {
-    #[no_mangle]
     fn test_i8x2_mixed_args(a: i8x2, c: i32, b: i8x2);
 }
 
 extern "unadjusted" {
-    #[no_mangle]
-    fn test_i8x2_arr(a: i8x2_arr);
+    fn test_i8x2_arr(a: i8x2);
 }
 
 extern "unadjusted" {
-    #[no_mangle]
     fn test_f32x2(a: f32x2);
 }
 
 extern "unadjusted" {
-    #[no_mangle]
-    fn test_f32x2_arr(a: f32x2_arr);
+    fn test_f32x2_arr(a: f32x2);
 }
 
 extern "unadjusted" {
-    #[no_mangle]
     fn test_simd(a: Simd<i32, 4>);
 }
 
 extern "unadjusted" {
-    #[no_mangle]
     fn test_simd_unaligned(a: Simd<i32, 3>);
 }
 
@@ -81,22 +65,22 @@ extern "unadjusted" {
 pub fn do_call() {
     unsafe {
         // CHECK: call void @test_i8x2(<2 x i8> <i8 32, i8 64>
-        test_i8x2(const { i8x2(32, 64) });
+        test_i8x2(const { i8x2([32, 64]) });
 
         // CHECK: call void @test_i8x2_two_args(<2 x i8> <i8 32, i8 64>, <2 x i8> <i8 8, i8 16>
-        test_i8x2_two_args(const { i8x2(32, 64) }, const { i8x2(8, 16) });
+        test_i8x2_two_args(const { i8x2([32, 64]) }, const { i8x2([8, 16]) });
 
         // CHECK: call void @test_i8x2_mixed_args(<2 x i8> <i8 32, i8 64>, i32 43, <2 x i8> <i8 8, i8 16>
-        test_i8x2_mixed_args(const { i8x2(32, 64) }, 43, const { i8x2(8, 16) });
+        test_i8x2_mixed_args(const { i8x2([32, 64]) }, 43, const { i8x2([8, 16]) });
 
         // CHECK: call void @test_i8x2_arr(<2 x i8> <i8 32, i8 64>
-        test_i8x2_arr(const { i8x2_arr([32, 64]) });
+        test_i8x2_arr(const { i8x2([32, 64]) });
 
         // CHECK: call void @test_f32x2(<2 x float> <float 0x3FD47AE140000000, float 0x3FE47AE140000000>
-        test_f32x2(const { f32x2(0.32, 0.64) });
+        test_f32x2(const { f32x2([0.32, 0.64]) });
 
         // CHECK: void @test_f32x2_arr(<2 x float> <float 0x3FD47AE140000000, float 0x3FE47AE140000000>
-        test_f32x2_arr(const { f32x2_arr([0.32, 0.64]) });
+        test_f32x2_arr(const { f32x2([0.32, 0.64]) });
 
         // CHECK: call void @test_simd(<4 x i32> <i32 2, i32 4, i32 6, i32 8>
         test_simd(const { Simd::<i32, 4>([2, 4, 6, 8]) });

diff --git a/tests/codegen/repr/transparent.rs b/tests/codegen/repr/transparent.rs
@@ -132,7 +132,7 @@ pub extern "C" fn test_Nested2(_: Nested2) -> Nested2 {
 }
 
 #[repr(simd)]
-struct f32x4(f32, f32, f32, f32);
+struct f32x4([f32; 4]);
 
 #[repr(transparent)]
 pub struct Vector(f32x4);

diff --git a/tests/codegen/simd-intrinsic/simd-intrinsic-float-abs.rs b/tests/codegen/simd-intrinsic/simd-intrinsic-float-abs.rs
@@ -7,23 +7,19 @@
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x2(pub f32, pub f32);
+pub struct f32x2(pub [f32; 2]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x4(pub f32, pub f32, pub f32, pub f32);
+pub struct f32x4(pub [f32; 4]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x8(pub f32, pub f32, pub f32, pub f32,
-                 pub f32, pub f32, pub f32, pub f32);
+pub struct f32x8(pub [f32; 8]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x16(pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32);
+pub struct f32x16(pub [f32; 16]);
 
 extern "rust-intrinsic" {
     fn simd_fabs<T>(x: T) -> T;
@@ -59,16 +55,15 @@ pub unsafe fn fabs_32x16(a: f32x16) -> f32x16 {
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x2(pub f64, pub f64);
+pub struct f64x2(pub [f64; 2]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x4(pub f64, pub f64, pub f64, pub f64);
+pub struct f64x4(pub [f64; 4]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x8(pub f64, pub f64, pub f64, pub f64,
-                 pub f64, pub f64, pub f64, pub f64);
+pub struct f64x8(pub [f64; 8]);
 
 // CHECK-LABEL: @fabs_64x4
 #[no_mangle]

diff --git a/tests/codegen/simd-intrinsic/simd-intrinsic-float-ceil.rs b/tests/codegen/simd-intrinsic/simd-intrinsic-float-ceil.rs
@@ -7,23 +7,19 @@
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x2(pub f32, pub f32);
+pub struct f32x2(pub [f32; 2]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x4(pub f32, pub f32, pub f32, pub f32);
+pub struct f32x4(pub [f32; 4]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x8(pub f32, pub f32, pub f32, pub f32,
-                 pub f32, pub f32, pub f32, pub f32);
+pub struct f32x8(pub [f32; 8]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x16(pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32);
+pub struct f32x16(pub [f32; 16]);
 
 extern "rust-intrinsic" {
     fn simd_ceil<T>(x: T) -> T;
@@ -59,16 +55,15 @@ pub unsafe fn ceil_32x16(a: f32x16) -> f32x16 {
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x2(pub f64, pub f64);
+pub struct f64x2(pub [f64; 2]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x4(pub f64, pub f64, pub f64, pub f64);
+pub struct f64x4(pub [f64; 4]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x8(pub f64, pub f64, pub f64, pub f64,
-                 pub f64, pub f64, pub f64, pub f64);
+pub struct f64x8(pub [f64; 8]);
 
 // CHECK-LABEL: @ceil_64x4
 #[no_mangle]

diff --git a/tests/codegen/simd-intrinsic/simd-intrinsic-float-cos.rs b/tests/codegen/simd-intrinsic/simd-intrinsic-float-cos.rs
@@ -7,23 +7,19 @@
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x2(pub f32, pub f32);
+pub struct f32x2(pub [f32; 2]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x4(pub f32, pub f32, pub f32, pub f32);
+pub struct f32x4(pub [f32; 4]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x8(pub f32, pub f32, pub f32, pub f32,
-                 pub f32, pub f32, pub f32, pub f32);
+pub struct f32x8(pub [f32; 8]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f32x16(pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32,
-                  pub f32, pub f32, pub f32, pub f32);
+pub struct f32x16(pub [f32; 16]);
 
 extern "rust-intrinsic" {
     fn simd_fcos<T>(x: T) -> T;
@@ -59,16 +55,15 @@ pub unsafe fn fcos_32x16(a: f32x16) -> f32x16 {
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x2(pub f64, pub f64);
+pub struct f64x2(pub [f64; 2]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x4(pub f64, pub f64, pub f64, pub f64);
+pub struct f64x4(pub [f64; 4]);
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
-pub struct f64x8(pub f64, pub f64, pub f64, pub f64,
-                 pub f64, pub f64, pub f64, pub f64);
+pub struct f64x8(pub [f64; 8]);
 
 // CHECK-LABEL: @fcos_64x4
 #[no_mangle]