Query-ify needs_gdb_debug_scripts_section

This ensures that a codegen unit DepNode does not have a direct
dependency on the crate's attributes

Author: Aaron1011

Diff for: compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs

@@ -7,14 +7,12 @@ use crate::common::CodegenCx;
 use crate::value::Value;
 use rustc_codegen_ssa::traits::*;
 use rustc_middle::bug;
-use rustc_session::config::DebugInfo;
-
-use rustc_span::symbol::sym;
+use rustc_span::def_id::LOCAL_CRATE;
 
 /// Inserts a side-effect free instruction sequence that makes sure that the
 /// .debug_gdb_scripts global is referenced, so it isn't removed by the linker.
 pub fn insert_reference_to_gdb_debug_scripts_section_global(bx: &mut Builder<'_, '_, '_>) {
-    if needs_gdb_debug_scripts_section(bx) {
+    if bx.tcx.needs_gdb_debug_scripts_section(LOCAL_CRATE) {
         let gdb_debug_scripts_section = get_or_insert_gdb_debug_scripts_section_global(bx);
         // Load just the first byte as that's all that's necessary to force
         // LLVM to keep around the reference to the global.
@@ -58,14 +56,3 @@ pub fn get_or_insert_gdb_debug_scripts_section_global(cx: &CodegenCx<'ll, '_>) -
         }
     })
 }
-
-pub fn needs_gdb_debug_scripts_section(cx: &CodegenCx<'_, '_>) -> bool {
-    let omit_gdb_pretty_printer_section = cx
-        .tcx
-        .sess
-        .contains_name(&cx.tcx.hir().krate_attrs(), sym::omit_gdb_pretty_printer_section);
-
-    !omit_gdb_pretty_printer_section
-        && cx.sess().opts.debuginfo != DebugInfo::None
-        && cx.sess().target.emit_debug_gdb_scripts
-}

Diff for: compiler/rustc_codegen_llvm/src/debuginfo/mod.rs

@@ -106,7 +106,7 @@ pub fn finalize(cx: &CodegenCx<'_, '_>) {
 
     debug!("finalize");
 
-    if gdb::needs_gdb_debug_scripts_section(cx) {
+    if cx.tcx.needs_gdb_debug_scripts_section(LOCAL_CRATE) {
         // Add a .debug_gdb_scripts section to this compile-unit. This will
         // cause GDB to try and load the gdb_load_rust_pretty_printers.py file,
         // which activates the Rust pretty printers for binary this section is

Diff for: compiler/rustc_codegen_ssa/src/base.rs

@@ -28,8 +28,9 @@ use rustc_middle::ty::layout::{FAT_PTR_ADDR, FAT_PTR_EXTRA};
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
 use rustc_session::cgu_reuse_tracker::CguReuse;
-use rustc_session::config::{self, EntryFnType};
+use rustc_session::config::{self, DebugInfo, EntryFnType};
 use rustc_session::Session;
+use rustc_span::sym;
 use rustc_target::abi::{Align, LayoutOf, VariantIdx};
 
 use std::cmp;
@@ -828,6 +829,17 @@ pub fn provide(providers: &mut Providers) {
         }
         tcx.sess.opts.optimize
     };
+
+    providers.needs_gdb_debug_scripts_section = |tcx, cnum| {
+        assert_eq!(cnum, LOCAL_CRATE);
+
+        let omit_gdb_pretty_printer_section =
+            tcx.sess.contains_name(&tcx.hir().krate_attrs(), sym::omit_gdb_pretty_printer_section);
+
+        !omit_gdb_pretty_printer_section
+            && tcx.sess.opts.debuginfo != DebugInfo::None
+            && tcx.sess.target.emit_debug_gdb_scripts
+    };
 }
 
 fn determine_cgu_reuse<'tcx>(tcx: TyCtxt<'tcx>, cgu: &CodegenUnit<'tcx>) -> CguReuse {

Diff for: compiler/rustc_middle/src/query/mod.rs

@@ -1214,6 +1214,13 @@ rustc_queries! {
         desc { "looking up the paths for extern crates" }
     }
 
+    /// Determines if we need to emit a GDB debug script section
+    /// during codegen for the current crate. The CrateNum
+    /// should always be LOCAL_CRATE
+    query needs_gdb_debug_scripts_section(_: CrateNum) -> bool {
+        desc { "determine if the current crate needs a gdb debug scripts section" }
+    }
+
     /// Given a crate and a trait, look up all impls of that trait in the crate.
     /// Return `(impl_id, self_ty)`.
     query implementations_of_trait(_: (CrateNum, DefId))