ABI checks: add support for tier2 arches

See #131800 for the data collection behind this change.

Also adds a test that exercise the "empty list of features" path.

4 files changed, 85 insertions, 21 deletions

diff --git a/compiler/rustc_monomorphize/messages.ftl b/compiler/rustc_monomorphize/messages.ftl
index 6da387bbebc..8528a2e68c0 100644
--- a/compiler/rustc_monomorphize/messages.ftl
+++ b/compiler/rustc_monomorphize/messages.ftl
@@ -1,12 +1,19 @@
 monomorphize_abi_error_disabled_vector_type_call =
-  ABI error: this function call uses a vector type that requires the `{$required_feature}` target feature, which is not enabled in the caller
+  this function call uses a SIMD vector type that (with the chosen ABI) requires the `{$required_feature}` target feature, which is not enabled in the caller
   .label = function called here
   .help = consider enabling it globally (`-C target-feature=+{$required_feature}`) or locally (`#[target_feature(enable="{$required_feature}")]`)
 monomorphize_abi_error_disabled_vector_type_def =
-  ABI error: this function definition uses a vector type that requires the `{$required_feature}` target feature, which is not enabled
+  this function definition uses a SIMD vector type that (with the chosen ABI) requires the `{$required_feature}` target feature, which is not enabled
   .label = function defined here
   .help = consider enabling it globally (`-C target-feature=+{$required_feature}`) or locally (`#[target_feature(enable="{$required_feature}")]`)
 
+monomorphize_abi_error_unsupported_vector_type_call =
+  this function call uses a SIMD vector type that is not currently supported with the chosen ABI
+  .label = function called here
+monomorphize_abi_error_unsupported_vector_type_def =
+  this function definition uses a SIMD vector type that is not currently supported with the chosen ABI
+  .label = function defined here
+
 monomorphize_couldnt_dump_mono_stats =
     unexpected error occurred while dumping monomorphization stats: {$error}
 
diff --git a/compiler/rustc_monomorphize/src/errors.rs b/compiler/rustc_monomorphize/src/errors.rs
index 5048a8d5d99..02865cad302 100644
--- a/compiler/rustc_monomorphize/src/errors.rs
+++ b/compiler/rustc_monomorphize/src/errors.rs
@@ -110,3 +110,17 @@ pub(crate) struct AbiErrorDisabledVectorTypeCall<'a> {
     pub span: Span,
     pub required_feature: &'a str,
 }
+
+#[derive(LintDiagnostic)]
+#[diag(monomorphize_abi_error_unsupported_vector_type_def)]
+pub(crate) struct AbiErrorUnsupportedVectorTypeDef {
+    #[label]
+    pub span: Span,
+}
+
+#[derive(LintDiagnostic)]
+#[diag(monomorphize_abi_error_unsupported_vector_type_call)]
+pub(crate) struct AbiErrorUnsupportedVectorTypeCall {
+    #[label]
+    pub span: Span,
+}
diff --git a/compiler/rustc_monomorphize/src/mono_checks/abi_check.rs b/compiler/rustc_monomorphize/src/mono_checks/abi_check.rs
index 221200e9497..d53595929e7 100644
--- a/compiler/rustc_monomorphize/src/mono_checks/abi_check.rs
+++ b/compiler/rustc_monomorphize/src/mono_checks/abi_check.rs
@@ -10,7 +10,10 @@ use rustc_span::{DUMMY_SP, Span, Symbol};
 use rustc_target::abi::call::{FnAbi, PassMode};
 use rustc_target::abi::{BackendRepr, RegKind};
 
-use crate::errors::{AbiErrorDisabledVectorTypeCall, AbiErrorDisabledVectorTypeDef};
+use crate::errors::{
+    AbiErrorDisabledVectorTypeCall, AbiErrorDisabledVectorTypeDef,
+    AbiErrorUnsupportedVectorTypeCall, AbiErrorUnsupportedVectorTypeDef,
+};
 
 fn uses_vector_registers(mode: &PassMode, repr: &BackendRepr) -> bool {
     match mode {
@@ -23,11 +26,15 @@ fn uses_vector_registers(mode: &PassMode, repr: &BackendRepr) -> bool {
     }
 }
 
+/// Checks whether a certain function ABI is compatible with the target features currently enabled
+/// for a certain function.
+/// If not, `emit_err` is called, with `Some(feature)` if a certain feature should be enabled and
+/// with `None` if no feature is known that would make the ABI compatible.
 fn do_check_abi<'tcx>(
     tcx: TyCtxt<'tcx>,
     abi: &FnAbi<'tcx, Ty<'tcx>>,
     target_feature_def: DefId,
-    mut emit_err: impl FnMut(&'static str),
+    mut emit_err: impl FnMut(Option<&'static str>),
 ) {
     let Some(feature_def) = tcx.sess.target.features_for_correct_vector_abi() else {
         return;
@@ -40,7 +47,7 @@ fn do_check_abi<'tcx>(
             let feature = match feature_def.iter().find(|(bits, _)| size.bits() <= *bits) {
                 Some((_, feature)) => feature,
                 None => {
-                    emit_err("<no available feature for this size>");
+                    emit_err(None);
                     continue;
                 }
             };
@@ -48,7 +55,7 @@ fn do_check_abi<'tcx>(
             if !tcx.sess.unstable_target_features.contains(&feature_sym)
                 && !codegen_attrs.target_features.iter().any(|x| x.name == feature_sym)
             {
-                emit_err(feature);
+                emit_err(Some(&feature));
             }
         }
     }
@@ -65,12 +72,21 @@ fn check_instance_abi<'tcx>(tcx: TyCtxt<'tcx>, instance: Instance<'tcx>) {
     };
     do_check_abi(tcx, abi, instance.def_id(), |required_feature| {
         let span = tcx.def_span(instance.def_id());
-        tcx.emit_node_span_lint(
-            ABI_UNSUPPORTED_VECTOR_TYPES,
-            CRATE_HIR_ID,
-            span,
-            AbiErrorDisabledVectorTypeDef { span, required_feature },
-        );
+        if let Some(required_feature) = required_feature {
+            tcx.emit_node_span_lint(
+                ABI_UNSUPPORTED_VECTOR_TYPES,
+                CRATE_HIR_ID,
+                span,
+                AbiErrorDisabledVectorTypeDef { span, required_feature },
+            );
+        } else {
+            tcx.emit_node_span_lint(
+                ABI_UNSUPPORTED_VECTOR_TYPES,
+                CRATE_HIR_ID,
+                span,
+                AbiErrorUnsupportedVectorTypeDef { span },
+            );
+        }
     })
 }
 
@@ -109,12 +125,21 @@ fn check_call_site_abi<'tcx>(
         return;
     };
     do_check_abi(tcx, callee_abi, caller.def_id(), |required_feature| {
-        tcx.emit_node_span_lint(
-            ABI_UNSUPPORTED_VECTOR_TYPES,
-            CRATE_HIR_ID,
-            span,
-            AbiErrorDisabledVectorTypeCall { span, required_feature },
-        );
+        if let Some(required_feature) = required_feature {
+            tcx.emit_node_span_lint(
+                ABI_UNSUPPORTED_VECTOR_TYPES,
+                CRATE_HIR_ID,
+                span,
+                AbiErrorDisabledVectorTypeCall { span, required_feature },
+            );
+        } else {
+            tcx.emit_node_span_lint(
+                ABI_UNSUPPORTED_VECTOR_TYPES,
+                CRATE_HIR_ID,
+                span,
+                AbiErrorUnsupportedVectorTypeCall { span },
+            );
+        }
     });
 }
 
diff --git a/compiler/rustc_target/src/target_features.rs b/compiler/rustc_target/src/target_features.rs
index b7588b01814..88536926b11 100644
--- a/compiler/rustc_target/src/target_features.rs
+++ b/compiler/rustc_target/src/target_features.rs
@@ -586,9 +586,20 @@ pub fn all_rust_features() -> impl Iterator<Item = (&'static str, Stability)> {
 // certain size to have their "proper" ABI on each architecture.
 // Note that they must be kept sorted by vector size.
 const X86_FEATURES_FOR_CORRECT_VECTOR_ABI: &'static [(u64, &'static str)] =
-    &[(128, "sse"), (256, "avx"), (512, "avx512f")];
+    &[(128, "sse"), (256, "avx"), (512, "avx512f")]; // FIXME: might need changes for AVX10.
 const AARCH64_FEATURES_FOR_CORRECT_VECTOR_ABI: &'static [(u64, &'static str)] = &[(128, "neon")];
 
+// We might want to add "helium" too.
+const ARM_FEATURES_FOR_CORRECT_VECTOR_ABI: &'static [(u64, &'static str)] = &[(128, "neon")];
+
+const POWERPC_FEATURES_FOR_CORRECT_VECTOR_ABI: &'static [(u64, &'static str)] = &[(128, "altivec")];
+const WASM_FEATURES_FOR_CORRECT_VECTOR_ABI: &'static [(u64, &'static str)] = &[(128, "simd128")];
+const S390X_FEATURES_FOR_CORRECT_VECTOR_ABI: &'static [(u64, &'static str)] = &[(128, "vector")];
+const RISCV_FEATURES_FOR_CORRECT_VECTOR_ABI: &'static [(u64, &'static str)] =
+    &[/*(64, "zvl64b"), */ (128, "v")];
+// Always warn on SPARC, as the necessary target features cannot be enabled in Rust at the moment.
+const SPARC_FEATURES_FOR_CORRECT_VECTOR_ABI: &'static [(u64, &'static str)] = &[/*(128, "vis")*/];
+
 impl super::spec::Target {
     pub fn rust_target_features(&self) -> &'static [(&'static str, Stability, ImpliedFeatures)] {
         match &*self.arch {
@@ -613,8 +624,15 @@ impl super::spec::Target {
     pub fn features_for_correct_vector_abi(&self) -> Option<&'static [(u64, &'static str)]> {
         match &*self.arch {
             "x86" | "x86_64" => Some(X86_FEATURES_FOR_CORRECT_VECTOR_ABI),
-            "aarch64" => Some(AARCH64_FEATURES_FOR_CORRECT_VECTOR_ABI),
-            // FIXME: add support for non-tier1 architectures
+            "aarch64" | "arm64ec" => Some(AARCH64_FEATURES_FOR_CORRECT_VECTOR_ABI),
+            "arm" => Some(ARM_FEATURES_FOR_CORRECT_VECTOR_ABI),
+            "powerpc" | "powerpc64" => Some(POWERPC_FEATURES_FOR_CORRECT_VECTOR_ABI),
+            "loongarch64" => Some(&[]), // on-stack ABI, so we complain about all by-val vectors
+            "riscv32" | "riscv64" => Some(RISCV_FEATURES_FOR_CORRECT_VECTOR_ABI),
+            "wasm32" | "wasm64" => Some(WASM_FEATURES_FOR_CORRECT_VECTOR_ABI),
+            "s390x" => Some(S390X_FEATURES_FOR_CORRECT_VECTOR_ABI),
+            "sparc" | "sparc64" => Some(SPARC_FEATURES_FOR_CORRECT_VECTOR_ABI),
+            // FIXME: add support for non-tier2 architectures
             _ => None,
         }
     }