rename needs_crate_hash to needs_hir_hash.

It's easy to confuse the functionality of `needs_crate_hash` with "is
the crate_hash query needed" right now. The function returns
whether we need to calculate the stable hash of various hir structs.

Author: susitsm

compiler/rustc_ast_lowering/src/lib.rs

@@ -563,7 +563,7 @@ pub fn lower_to_hir(tcx: TyCtxt<'_>, (): ()) -> mid_hir::Crate<'_> {
 
     // Don't hash unless necessary, because it's expensive.
     let opt_hir_hash =
-        if tcx.needs_crate_hash() { Some(compute_hir_hash(tcx, &owners)) } else { None };
+        if tcx.needs_hir_hash() { Some(compute_hir_hash(tcx, &owners)) } else { None };
 
     let delayed_resolver = Steal::new((resolver, krate));
     mid_hir::Crate::new(owners, delayed_ids, delayed_resolver, opt_hir_hash)

compiler/rustc_middle/src/hir/mod.rs

@@ -237,7 +237,7 @@ impl<'tcx> TyCtxt<'tcx> {
         attrs: &SortedMap<ItemLocalId, &[Attribute]>,
         define_opaque: Option<&[(Span, LocalDefId)]>,
     ) -> Hashes {
-        if !self.needs_crate_hash() {
+        if !self.needs_hir_hash() {
             return Hashes { opt_hash_including_bodies: None, attrs_hash: None };
         }
 

compiler/rustc_middle/src/ty/context.rs

@@ -1136,12 +1136,12 @@ impl<'tcx> TyCtxt<'tcx> {
         })
     }
 
-    pub fn needs_crate_hash(self) -> bool {
-        // Why is the crate hash needed for these configurations?
+    pub fn needs_hir_hash(self) -> bool {
+        // Why is the hir hash needed for these configurations?
         // - debug_assertions: for the "fingerprint the result" check in
         //   `rustc_query_impl::execution::execute_job`.
         // - incremental: for query lookups.
-        // - needs_metadata: for putting into crate metadata.
+        // - needs_metadata: it is included in the crate metadata through the crate_hash query
         // - instrument_coverage: for putting into coverage data (see
         //   `hash_mir_source`).
         // - metrics_dir: metrics use the strict version hash in the filenames