ast_passes: unsupported arch w/ scalable vectors

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -1371,11 +1371,16 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
             ItemKind::Struct(ident, generics, vdata) => {
                 self.with_tilde_const(Some(TildeConstReason::Struct { span: item.span }), |this| {
                     // Scalable vectors can only be tuple structs
-                    let is_scalable_vector =
-                        item.attrs.iter().any(|attr| attr.has_name(sym::rustc_scalable_vector));
-                    if is_scalable_vector && !matches!(vdata, VariantData::Tuple(..)) {
-                        this.dcx()
-                            .emit_err(errors::ScalableVectorNotTupleStruct { span: item.span });
+                    let scalable_vector_attr =
+                        item.attrs.iter().find(|attr| attr.has_name(sym::rustc_scalable_vector));
+                    if let Some(attr) = scalable_vector_attr {
+                        if !matches!(vdata, VariantData::Tuple(..)) {
+                            this.dcx()
+                                .emit_err(errors::ScalableVectorNotTupleStruct { span: item.span });
+                        }
+                        if !self.sess.target.arch.supports_scalable_vectors() {
+                            this.dcx().emit_err(errors::ScalableVectorBadArch { span: attr.span });
+                        }
                     }
 
                     match vdata {

compiler/rustc_ast_passes/src/errors.rs

@@ -1133,3 +1133,10 @@ pub(crate) struct ScalableVectorNotTupleStruct {
     #[primary_span]
     pub span: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag("scalable vectors are not supported on this architecture")]
+pub(crate) struct ScalableVectorBadArch {
+    #[primary_span]
+    pub span: Span,
+}

compiler/rustc_target/src/spec/mod.rs

@@ -1956,6 +1956,19 @@ impl Arch {
             | X86_64 | Xtensa => true,
         }
     }
+
+    /// Whether `#[rustc_scalable_vector]` is supported for a target architecture
+    pub fn supports_scalable_vectors(&self) -> bool {
+        use Arch::*;
+
+        match self {
+            AArch64 | RiscV32 | RiscV64 => true,
+            AmdGpu | Arm | Arm64EC | Avr | Bpf | CSky | Hexagon | LoongArch32 | LoongArch64
+            | M68k | Mips | Mips32r6 | Mips64 | Mips64r6 | Msp430 | Nvptx64 | PowerPC
+            | PowerPC64 | S390x | Sparc | Sparc64 | SpirV | Wasm32 | Wasm64 | X86 | X86_64
+            | Xtensa | Other(_) => false,
+        }
+    }
 }
 
 crate::target_spec_enum! {

src/tools/compiletest/src/directives/directive_names.rs

@@ -105,6 +105,7 @@ pub(crate) const KNOWN_DIRECTIVE_NAMES: &[&str] = &[
     "ignore-powerpc",
     "ignore-powerpc64",
     "ignore-remote",
+    "ignore-riscv32",
     "ignore-riscv64",
     "ignore-rustc-debug-assertions",
     "ignore-rustc_abi-x86-sse2",

tests/ui/scalable-vectors/bad-architectures.rs

@@ -0,0 +1,13 @@
+//@ ignore-aarch64
+//@ ignore-riscv32
+//@ ignore-riscv64
+
+// Confirm that non-AArch64 and non-RISC-V targets error when compiling scalable vectors
+// (see #153593)
+
+#![crate_type = "lib"]
+#![feature(rustc_attrs)]
+
+#[rustc_scalable_vector(4)]
+//~^ ERROR: scalable vectors are not supported on this architecture
+struct ScalableVec(i32);

tests/ui/scalable-vectors/bad-architectures.stderr

@@ -0,0 +1,8 @@
+error: scalable vectors are not supported on this architecture
+  --> $DIR/bad-architectures.rs:11:1
+   |
+LL | #[rustc_scalable_vector(4)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 1 previous error
+

tests/ui/scalable-vectors/fn-trait.rs

@@ -1,3 +1,4 @@
+//@ only-aarch64
 #![allow(internal_features)]
 #![feature(rustc_attrs)]
 

tests/ui/scalable-vectors/fn-trait.stderr

@@ -1,5 +1,5 @@
 error: scalable vectors cannot be tuple fields
-  --> $DIR/fn-trait.rs:9:8
+  --> $DIR/fn-trait.rs:10:8
    |
 LL |     T: Fn(ScalableSimdFloat),
    |        ^^^^^^^^^^^^^^^^^^^^^

tests/ui/scalable-vectors/illegal_init.rs → tests/ui/scalable-vectors/illegal-init.rs

@@ -1,3 +1,4 @@
+//@ only-aarch64
 #![allow(incomplete_features, internal_features)]
 #![feature(rustc_attrs)]
 

tests/ui/scalable-vectors/illegal_init.stderr → tests/ui/scalable-vectors/illegal-init.stderr

@@ -1,5 +1,5 @@
 error: scalable vector types cannot be initialised using their constructor
-  --> $DIR/illegal_init.rs:8:15
+  --> $DIR/illegal-init.rs:9:15
    |
 LL |     let foo = svint32_t(1);
    |               ^^^^^^^^^ you can create scalable vectors using intrinsics

tests/ui/scalable-vectors/illformed-element-type.rs

@@ -1,4 +1,5 @@
 //@ compile-flags: --crate-type=lib
+//@ only-aarch64
 #![allow(internal_features)]
 #![feature(extern_types)]
 #![feature(never_type)]

tests/ui/scalable-vectors/illformed-element-type.stderr

@@ -1,117 +1,117 @@
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:15:1
+  --> $DIR/illformed-element-type.rs:16:1
    |
 LL | struct TyChar(char);
    | ^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:19:1
+  --> $DIR/illformed-element-type.rs:20:1
    |
 LL | struct TyConstPtr(*const u8);
    | ^^^^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:23:1
+  --> $DIR/illformed-element-type.rs:24:1
    |
 LL | struct TyMutPtr(*mut u8);
    | ^^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:27:1
+  --> $DIR/illformed-element-type.rs:28:1
    |
 LL | struct TyStruct(Foo);
    | ^^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:31:1
+  --> $DIR/illformed-element-type.rs:32:1
    |
 LL | struct TyEnum(Bar);
    | ^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:35:1
+  --> $DIR/illformed-element-type.rs:36:1
    |
 LL | struct TyUnion(Baz);
    | ^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:39:1
+  --> $DIR/illformed-element-type.rs:40:1
    |
 LL | struct TyForeign(Qux);
    | ^^^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:43:1
+  --> $DIR/illformed-element-type.rs:44:1
    |
 LL | struct TyArray([u32; 4]);
    | ^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:47:1
+  --> $DIR/illformed-element-type.rs:48:1
    |
 LL | struct TySlice([u32]);
    | ^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:51:1
+  --> $DIR/illformed-element-type.rs:52:1
    |
 LL | struct TyRef<'a>(&'a u32);
    | ^^^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:55:1
+  --> $DIR/illformed-element-type.rs:56:1
    |
 LL | struct TyFnPtr(fn(u32) -> u32);
    | ^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:59:1
+  --> $DIR/illformed-element-type.rs:60:1
    |
 LL | struct TyDyn(dyn std::io::Write);
    | ^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:63:1
+  --> $DIR/illformed-element-type.rs:64:1
    |
 LL | struct TyNever(!);
    | ^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:67:1
+  --> $DIR/illformed-element-type.rs:68:1
    |
 LL | struct TyTuple((u32, u32));
    | ^^^^^^^^^^^^^^
    |
    = help: only `u*`, `i*`, `f*` and `bool` types are accepted
 
 error: element type of a scalable vector must be a primitive scalar
-  --> $DIR/illformed-element-type.rs:77:1
+  --> $DIR/illformed-element-type.rs:78:1
    |
 LL | struct TyInvalidAlias(InvalidAlias);
    | ^^^^^^^^^^^^^^^^^^^^^

tests/ui/scalable-vectors/illformed-tuples-of-scalable-vectors.rs

@@ -1,4 +1,5 @@
 //@ compile-flags: --crate-type=lib
+//@ only-aarch64
 #![allow(internal_features)]
 #![feature(rustc_attrs)]
 

tests/ui/scalable-vectors/illformed-tuples-of-scalable-vectors.stderr

@@ -1,35 +1,35 @@
 error: scalable vectors must be tuple structs
-  --> $DIR/illformed-tuples-of-scalable-vectors.rs:15:1
+  --> $DIR/illformed-tuples-of-scalable-vectors.rs:16:1
    |
 LL | struct Struct { x: ValidI64, y: ValidI64 }
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: all fields in a scalable vector struct must be the same type
-  --> $DIR/illformed-tuples-of-scalable-vectors.rs:19:39
+  --> $DIR/illformed-tuples-of-scalable-vectors.rs:20:39
    |
 LL | struct DifferentVectorTypes(ValidI64, ValidI32);
    |                                       ^^^^^^^^
 
 error: scalable vector structs can only have scalable vector fields
-  --> $DIR/illformed-tuples-of-scalable-vectors.rs:23:23
+  --> $DIR/illformed-tuples-of-scalable-vectors.rs:24:23
    |
 LL | struct NonVectorTypes(u32, u64);
    |                       ^^^
 
 error: scalable vector structs can only have scalable vector fields
-  --> $DIR/illformed-tuples-of-scalable-vectors.rs:27:32
+  --> $DIR/illformed-tuples-of-scalable-vectors.rs:28:32
    |
 LL | struct DifferentNonVectorTypes(u32, u64);
    |                                ^^^
 
 error: scalable vector structs can only have scalable vector fields
-  --> $DIR/illformed-tuples-of-scalable-vectors.rs:31:34
+  --> $DIR/illformed-tuples-of-scalable-vectors.rs:32:34
    |
 LL | struct SomeVectorTypes(ValidI64, u64);
    |                                  ^^^
 
 error: scalable vector structs cannot contain other scalable vector structs
-  --> $DIR/illformed-tuples-of-scalable-vectors.rs:35:20
+  --> $DIR/illformed-tuples-of-scalable-vectors.rs:36:20
    |
 LL | struct NestedTuple(ValidTuple, ValidTuple);
    |                    ^^^^^^^^^^

tests/ui/scalable-vectors/illformed-within-types.rs

@@ -1,4 +1,5 @@
 //@ compile-flags: --crate-type=lib
+//@ only-aarch64
 #![allow(internal_features)]
 #![feature(rustc_attrs)]
 

tests/ui/scalable-vectors/illformed-within-types.stderr

@@ -1,29 +1,29 @@
 error: scalable vectors cannot be fields of a struct
-  --> $DIR/illformed-within-types.rs:9:8
+  --> $DIR/illformed-within-types.rs:10:8
    |
 LL |     x: ValidI64,
    |        ^^^^^^^^
 
 error: scalable vectors cannot be tuple fields
-  --> $DIR/illformed-within-types.rs:11:15
+  --> $DIR/illformed-within-types.rs:12:15
    |
 LL |     in_tuple: (ValidI64,),
    |               ^^^^^^^^^^^
 
 error: scalable vectors cannot be fields of a struct
-  --> $DIR/illformed-within-types.rs:15:20
+  --> $DIR/illformed-within-types.rs:16:20
    |
 LL | struct TupleStruct(ValidI64);
    |                    ^^^^^^^^
 
 error: scalable vectors cannot be fields of a variant
-  --> $DIR/illformed-within-types.rs:19:26
+  --> $DIR/illformed-within-types.rs:20:26
    |
 LL |     StructVariant { _ty: ValidI64 },
    |                          ^^^^^^^^
 
 error: scalable vectors cannot be fields of a variant
-  --> $DIR/illformed-within-types.rs:21:18
+  --> $DIR/illformed-within-types.rs:22:18
    |
 LL |     TupleVariant(ValidI64),
    |                  ^^^^^^^^

tests/ui/scalable-vectors/illformed.rs

@@ -1,4 +1,5 @@
 //@ compile-flags: --crate-type=lib
+//@ only-aarch64
 #![allow(internal_features)]
 #![feature(rustc_attrs)]