Auto merge of #132736 - matthiaskrgr:rollup-66naqwb, r=matthiaskrgr

Rollup of 4 pull requests

Successful merges:

 - #132638 (Remove fixme comment about clobber_abi on PowerPC)
 - #132726 (Remove unused intercrate dependencies)
 - #132729 (Make fn_abi_sanity_check a bit stricter)
 - #132734 ( remove 'platform-intrinsic' ABI leftovers)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

Cargo.lock

@@ -3274,7 +3274,6 @@ name = "rustc_ast_lowering"
 version = "0.0.0"
 dependencies = [
  "rustc_ast",
- "rustc_ast_pretty",
  "rustc_data_structures",
  "rustc_errors",
  "rustc_fluent_macro",
@@ -3469,7 +3468,6 @@ dependencies = [
  "rustc_macros",
  "rustc_metadata",
  "rustc_middle",
- "rustc_monomorphize",
  "rustc_query_system",
  "rustc_serialize",
  "rustc_session",
@@ -3745,7 +3743,6 @@ dependencies = [
  "rustc_feature",
  "rustc_fluent_macro",
  "rustc_hir",
- "rustc_hir_pretty",
  "rustc_index",
  "rustc_infer",
  "rustc_lint_defs",
@@ -3793,7 +3790,6 @@ dependencies = [
  "rustc_middle",
  "rustc_session",
  "rustc_span",
- "rustc_target",
  "rustc_trait_selection",
  "rustc_type_ir",
  "smallvec",
@@ -3853,9 +3849,7 @@ dependencies = [
  "rustc_index",
  "rustc_macros",
  "rustc_middle",
- "rustc_next_trait_solver",
  "rustc_span",
- "rustc_target",
  "rustc_type_ir",
  "smallvec",
  "thin-vec",
@@ -3934,7 +3928,6 @@ dependencies = [
  "rustc_feature",
  "rustc_fluent_macro",
  "rustc_hir",
- "rustc_hir_pretty",
  "rustc_index",
  "rustc_infer",
  "rustc_macros",
@@ -4162,7 +4155,6 @@ dependencies = [
 name = "rustc_next_trait_solver"
 version = "0.0.0"
 dependencies = [
- "bitflags 2.6.0",
  "derive-where",
  "rustc_ast_ir",
  "rustc_data_structures",
@@ -4458,9 +4450,7 @@ dependencies = [
  "object 0.36.4",
  "rustc_abi",
  "rustc_data_structures",
- "rustc_feature",
  "rustc_fs_util",
- "rustc_index",
  "rustc_macros",
  "rustc_serialize",
  "rustc_span",
@@ -4492,8 +4482,6 @@ dependencies = [
  "rustc_middle",
  "rustc_next_trait_solver",
  "rustc_parse_format",
- "rustc_query_system",
- "rustc_serialize",
  "rustc_session",
  "rustc_span",
  "rustc_transmute",

compiler/rustc/src/main.rs

@@ -1,5 +1,7 @@
 // We need this feature as it changes `dylib` linking behavior and allows us to link to `rustc_driver`.
 #![feature(rustc_private)]
+// Several crates are depended upon but unused so that they are present in the sysroot
+#![expect(unused_crate_dependencies)]
 
 // A note about jemalloc: rustc uses jemalloc when built for CI and
 // distribution. The obvious way to do this is with the `#[global_allocator]`

compiler/rustc_ast_lowering/Cargo.toml

@@ -9,7 +9,6 @@ doctest = false
 [dependencies]
 # tidy-alphabetical-start
 rustc_ast = { path = "../rustc_ast" }
-rustc_ast_pretty = { path = "../rustc_ast_pretty" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_errors = { path = "../rustc_errors" }
 rustc_fluent_macro = { path = "../rustc_fluent_macro" }

compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs

@@ -1,4 +1,4 @@
-//! Codegen of intrinsics. This includes `extern "rust-intrinsic"`, `extern "platform-intrinsic"`
+//! Codegen of intrinsics. This includes `extern "rust-intrinsic"`,
 //! and LLVM intrinsics that have symbol names starting with `llvm.`.
 
 macro_rules! intrinsic_args {

compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs

@@ -1,4 +1,4 @@
-//! Codegen `extern "platform-intrinsic"` intrinsics.
+//! Codegen SIMD intrinsics.
 
 use cranelift_codegen::ir::immediates::Offset32;
 use rustc_target::abi::Endian;

compiler/rustc_codegen_ssa/Cargo.toml

@@ -28,7 +28,6 @@ rustc_index = { path = "../rustc_index" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_metadata = { path = "../rustc_metadata" }
 rustc_middle = { path = "../rustc_middle" }
-rustc_monomorphize = { path = "../rustc_monomorphize" }
 rustc_query_system = { path = "../rustc_query_system" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }

compiler/rustc_hir_analysis/Cargo.toml

@@ -19,7 +19,6 @@ rustc_errors = { path = "../rustc_errors" }
 rustc_feature = { path = "../rustc_feature" }
 rustc_fluent_macro = { path = "../rustc_fluent_macro" }
 rustc_hir = { path = "../rustc_hir" }
-rustc_hir_pretty = { path = "../rustc_hir_pretty" }
 rustc_index = { path = "../rustc_index" }
 rustc_infer = { path = "../rustc_infer" }
 rustc_lint_defs = { path = "../rustc_lint_defs" }

compiler/rustc_hir_analysis/src/check/intrinsic.rs

@@ -1,5 +1,4 @@
-//! Type-checking for the rust-intrinsic and platform-intrinsic
-//! intrinsics that the compiler exposes.
+//! Type-checking for the rust-intrinsic intrinsics that the compiler exposes.
 
 use rustc_abi::ExternAbi;
 use rustc_errors::codes::*;

compiler/rustc_hir_typeck/Cargo.toml

@@ -23,7 +23,6 @@ rustc_macros = { path = "../rustc_macros" }
 rustc_middle = { path = "../rustc_middle" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
-rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_type_ir = { path = "../rustc_type_ir" }
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }

compiler/rustc_infer/Cargo.toml

@@ -16,9 +16,7 @@ rustc_hir = { path = "../rustc_hir" }
 rustc_index = { path = "../rustc_index" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_middle = { path = "../rustc_middle" }
-rustc_next_trait_solver = { path = "../rustc_next_trait_solver" }
 rustc_span = { path = "../rustc_span" }
-rustc_target = { path = "../rustc_target" }
 rustc_type_ir = { path = "../rustc_type_ir" }
 smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
 thin-vec = "0.2.12"

compiler/rustc_lint/Cargo.toml

@@ -14,7 +14,6 @@ rustc_errors = { path = "../rustc_errors" }
 rustc_feature = { path = "../rustc_feature" }
 rustc_fluent_macro = { path = "../rustc_fluent_macro" }
 rustc_hir = { path = "../rustc_hir" }
-rustc_hir_pretty = { path = "../rustc_hir_pretty" }
 rustc_index = { path = "../rustc_index" }
 rustc_infer = { path = "../rustc_infer" }
 rustc_macros = { path = "../rustc_macros" }

compiler/rustc_middle/src/ty/instance.rs

@@ -71,7 +71,7 @@ pub enum InstanceKind<'tcx> {
     /// - coroutines
     Item(DefId),
 
-    /// An intrinsic `fn` item (with `"rust-intrinsic"` or `"platform-intrinsic"` ABI).
+    /// An intrinsic `fn` item (with `"rust-intrinsic"` ABI).
     ///
     /// Alongside `Virtual`, this is the only `InstanceKind` that does not have its own callable MIR.
     /// Instead, codegen and const eval "magically" evaluate calls to intrinsics purely in the

compiler/rustc_next_trait_solver/Cargo.toml

@@ -5,7 +5,6 @@ edition = "2021"
 
 [dependencies]
 # tidy-alphabetical-start
-bitflags = "2.4.1"
 derive-where = "1.2.7"
 rustc_ast_ir = { path = "../rustc_ast_ir", default-features = false }
 rustc_data_structures = { path = "../rustc_data_structures", optional = true }

compiler/rustc_target/Cargo.toml

@@ -8,9 +8,7 @@ edition = "2021"
 bitflags = "2.4.1"
 rustc_abi = { path = "../rustc_abi" }
 rustc_data_structures = { path = "../rustc_data_structures" }
-rustc_feature = { path = "../rustc_feature" }
 rustc_fs_util = { path = "../rustc_fs_util" }
-rustc_index = { path = "../rustc_index" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_span = { path = "../rustc_span" }

compiler/rustc_target/src/asm/mod.rs

@@ -1128,6 +1128,21 @@ impl InlineAsmClobberAbi {
             },
             InlineAsmClobberAbi::PowerPC => clobbered_regs! {
                 PowerPC PowerPCInlineAsmReg {
+                    // Refs:
+                    // - PPC32 SysV: "3.2. Function Calling Sequence" in Power Architecture® 32-bit Application Binary Interface Supplement 1.0 - Linux® & Embedded
+                    //   https://web.archive.org/web/20120608163804/https://www.power.org/resources/downloads/Power-Arch-32-bit-ABI-supp-1.0-Unified.pdf
+                    // - PPC64 ELFv1: "3.2. Function Calling Sequence" in 64-bit PowerPC ELF Application Binary Interface Supplement 1.9
+                    //   https://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html#FUNC-CALL
+                    // - PPC64 ELFv2: "2.2 Function Calling Sequence" in 64-Bit ELF V2 ABI Specification: Power Architecture, Revision 1.5
+                    //   https://openpowerfoundation.org/specifications/64bitelfabi/
+                    // - AIX:
+                    //   - Register usage and conventions
+                    //     https://www.ibm.com/docs/en/aix/7.3?topic=overview-register-usage-conventions
+                    //   - Special registers in the PowerPC®
+                    //     https://www.ibm.com/docs/en/aix/7.3?topic=overview-special-registers-in-powerpc
+                    //   - AIX vector programming
+                    //     https://www.ibm.com/docs/en/aix/7.3?topic=concepts-aix-vector-programming
+
                     // r0, r3-r12
                     r0,
                     r3, r4, r5, r6, r7,
@@ -1138,8 +1153,6 @@ impl InlineAsmClobberAbi {
                     f8, f9, f10, f11, f12, f13,
 
                     // v0-v19
-                    // FIXME: PPC32 SysV ABI does not mention vector registers processing.
-                    // https://refspecs.linuxfoundation.org/elf/elfspec_ppc.pdf
                     v0, v1, v2, v3, v4, v5, v6, v7,
                     v8, v9, v10, v11, v12, v13, v14,
                     v15, v16, v17, v18, v19,

compiler/rustc_trait_selection/Cargo.toml

@@ -19,8 +19,6 @@ rustc_macros = { path = "../rustc_macros" }
 rustc_middle = { path = "../rustc_middle" }
 rustc_next_trait_solver = { path = "../rustc_next_trait_solver" }
 rustc_parse_format = { path = "../rustc_parse_format" }
-rustc_query_system = { path = "../rustc_query_system" }
-rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_transmute = { path = "../rustc_transmute", features = ["rustc"] }

compiler/rustc_ty_utils/src/abi.rs

@@ -463,43 +463,64 @@ fn fn_abi_sanity_check<'tcx>(
         arg: &ArgAbi<'tcx, Ty<'tcx>>,
     ) {
         let tcx = cx.tcx();
+
+        if spec_abi == ExternAbi::Rust
+            || spec_abi == ExternAbi::RustCall
+            || spec_abi == ExternAbi::RustCold
+        {
+            if arg.layout.is_zst() {
+                // Casting closures to function pointers depends on ZST closure types being
+                // omitted entirely in the calling convention.
+                assert!(arg.is_ignore());
+            }
+            if let PassMode::Indirect { on_stack, .. } = arg.mode {
+                assert!(!on_stack, "rust abi shouldn't use on_stack");
+            }
+        }
+
         match &arg.mode {
-            PassMode::Ignore => {}
+            PassMode::Ignore => {
+                assert!(arg.layout.is_zst() || arg.layout.is_uninhabited());
+            }
             PassMode::Direct(_) => {
                 // Here the Rust type is used to determine the actual ABI, so we have to be very
-                // careful. Scalar/ScalarPair is fine, since backends will generally use
-                // `layout.abi` and ignore everything else. We should just reject `Aggregate`
-                // entirely here, but some targets need to be fixed first.
-                if matches!(arg.layout.backend_repr, BackendRepr::Memory { .. }) {
-                    // For an unsized type we'd only pass the sized prefix, so there is no universe
-                    // in which we ever want to allow this.
-                    assert!(
-                        arg.layout.is_sized(),
-                        "`PassMode::Direct` for unsized type in ABI: {:#?}",
-                        fn_abi
-                    );
-                    // This really shouldn't happen even for sized aggregates, since
-                    // `immediate_llvm_type` will use `layout.fields` to turn this Rust type into an
-                    // LLVM type. This means all sorts of Rust type details leak into the ABI.
-                    // However wasm sadly *does* currently use this mode so we have to allow it --
-                    // but we absolutely shouldn't let any more targets do that.
-                    // (Also see <https://github.com/rust-lang/rust/issues/115666>.)
-                    //
-                    // The unstable abi `PtxKernel` also uses Direct for now.
-                    // It needs to switch to something else before stabilization can happen.
-                    // (See issue: https://github.com/rust-lang/rust/issues/117271)
-                    assert!(
-                        matches!(&*tcx.sess.target.arch, "wasm32" | "wasm64")
-                            || matches!(spec_abi, ExternAbi::PtxKernel | ExternAbi::Unadjusted),
-                        "`PassMode::Direct` for aggregates only allowed for \"unadjusted\" and \"ptx-kernel\" functions and on wasm\n\
+                // careful. Scalar/Vector is fine, since backends will generally use
+                // `layout.backend_repr` and ignore everything else. We should just reject
+                //`Aggregate` entirely here, but some targets need to be fixed first.
+                match arg.layout.backend_repr {
+                    BackendRepr::Uninhabited
+                    | BackendRepr::Scalar(_)
+                    | BackendRepr::Vector { .. } => {}
+                    BackendRepr::ScalarPair(..) => {
+                        panic!("`PassMode::Direct` used for ScalarPair type {}", arg.layout.ty)
+                    }
+                    BackendRepr::Memory { sized } => {
+                        // For an unsized type we'd only pass the sized prefix, so there is no universe
+                        // in which we ever want to allow this.
+                        assert!(sized, "`PassMode::Direct` for unsized type in ABI: {:#?}", fn_abi);
+                        // This really shouldn't happen even for sized aggregates, since
+                        // `immediate_llvm_type` will use `layout.fields` to turn this Rust type into an
+                        // LLVM type. This means all sorts of Rust type details leak into the ABI.
+                        // However wasm sadly *does* currently use this mode so we have to allow it --
+                        // but we absolutely shouldn't let any more targets do that.
+                        // (Also see <https://github.com/rust-lang/rust/issues/115666>.)
+                        //
+                        // The unstable abi `PtxKernel` also uses Direct for now.
+                        // It needs to switch to something else before stabilization can happen.
+                        // (See issue: https://github.com/rust-lang/rust/issues/117271)
+                        assert!(
+                            matches!(&*tcx.sess.target.arch, "wasm32" | "wasm64")
+                                || matches!(spec_abi, ExternAbi::PtxKernel | ExternAbi::Unadjusted),
+                            "`PassMode::Direct` for aggregates only allowed for \"unadjusted\" and \"ptx-kernel\" functions and on wasm\n\
                           Problematic type: {:#?}",
-                        arg.layout,
-                    );
+                            arg.layout,
+                        );
+                    }
                 }
             }
             PassMode::Pair(_, _) => {
-                // Similar to `Direct`, we need to make sure that backends use `layout.abi` and
-                // ignore the rest of the layout.
+                // Similar to `Direct`, we need to make sure that backends use `layout.backend_repr`
+                // and ignore the rest of the layout.
                 assert!(
                     matches!(arg.layout.backend_repr, BackendRepr::ScalarPair(..)),
                     "PassMode::Pair for type {}",