ICH: Replace old, transitive metadata hashing with direct hashing approach.

Instead of collecting all potential inputs to some metadata entry and
hashing those, we directly hash the values we are storing in metadata.
This is more accurate and doesn't suffer from quadratic blow-up when
many entries have the same dependencies.

1 files changed, 75 insertions, 15 deletions

diff --git a/src/test/incremental/hashes/struct_defs.rs b/src/test/incremental/hashes/struct_defs.rs
index 2d79987823f..17a5dc16783 100644
--- a/src/test/incremental/hashes/struct_defs.rs
+++ b/src/test/incremental/hashes/struct_defs.rs
@@ -62,9 +62,13 @@ struct TupleStructFieldType(i32);
 #[cfg(not(cfail1))]
 #[rustc_dirty(label="Hir", cfg="cfail2")]
 #[rustc_clean(label="Hir", cfg="cfail3")]
-#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct TupleStructFieldType(u32);
+struct TupleStructFieldType(
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    u32
+);
 
 
 // Tuple Struct Add Field ------------------------------------------------------
@@ -77,7 +81,13 @@ struct TupleStructAddField(i32);
 #[rustc_clean(label="Hir", cfg="cfail3")]
 #[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct TupleStructAddField(i32, u32);
+struct TupleStructAddField(
+    #[rustc_metadata_clean(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    i32,
+    #[rustc_metadata_clean(cfg="cfail3")]
+    u32
+);
 
 
 // Tuple Struct Field Visibility -----------------------------------------------
@@ -101,9 +111,13 @@ struct RecordStructFieldType { x: f32 }
 #[cfg(not(cfail1))]
 #[rustc_dirty(label="Hir", cfg="cfail2")]
 #[rustc_clean(label="Hir", cfg="cfail3")]
-#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct RecordStructFieldType { x: u64 }
+struct RecordStructFieldType {
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    x: u64
+}
 
 
 // Record Struct Field Name ----------------------------------------------------
@@ -129,7 +143,12 @@ struct RecordStructAddField { x: f32 }
 #[rustc_clean(label="Hir", cfg="cfail3")]
 #[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct RecordStructAddField { x: f32, y: () }
+struct RecordStructAddField {
+    #[rustc_metadata_clean(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    x: f32,
+    #[rustc_metadata_clean(cfg="cfail3")]
+    y: () }
 
 
 // Record Struct Field Visibility ----------------------------------------------
@@ -142,7 +161,11 @@ struct RecordStructFieldVisibility { x: f32 }
 #[rustc_clean(label="Hir", cfg="cfail3")]
 #[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct RecordStructFieldVisibility { pub x: f32 }
+struct RecordStructFieldVisibility {
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    pub x: f32
+}
 
 
 // Add Lifetime Parameter ------------------------------------------------------
@@ -168,7 +191,14 @@ struct AddLifetimeParameterBound<'a, 'b>(&'a f32, &'b f64);
 #[rustc_clean(label="Hir", cfg="cfail3")]
 #[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct AddLifetimeParameterBound<'a, 'b: 'a>(&'a f32, &'b f64);
+struct AddLifetimeParameterBound<'a, 'b: 'a>(
+    #[rustc_metadata_clean(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    &'a f32,
+    #[rustc_metadata_clean(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    &'b f64
+);
 
 #[cfg(cfail1)]
 struct AddLifetimeParameterBoundWhereClause<'a, 'b>(&'a f32, &'b f64);
@@ -178,7 +208,13 @@ struct AddLifetimeParameterBoundWhereClause<'a, 'b>(&'a f32, &'b f64);
 #[rustc_clean(label="Hir", cfg="cfail3")]
 #[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct AddLifetimeParameterBoundWhereClause<'a, 'b>(&'a f32, &'b f64)
+struct AddLifetimeParameterBoundWhereClause<'a, 'b>(
+    #[rustc_metadata_clean(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    &'a f32,
+    #[rustc_metadata_clean(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    &'b f64)
     where 'b: 'a;
 
 
@@ -192,7 +228,16 @@ struct AddTypeParameter<T1>(T1, T1);
 #[rustc_clean(label="Hir", cfg="cfail3")]
 #[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct AddTypeParameter<T1, T2>(T1, T2);
+struct AddTypeParameter<T1, T2>(
+     // The field contains the parent's Generics, so it's dirty even though its
+     // type hasn't changed.
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    T1,
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    T2
+);
 
 
 // Add Type Parameter Bound ----------------------------------------------------
@@ -205,7 +250,11 @@ struct AddTypeParameterBound<T>(T);
 #[rustc_clean(label="Hir", cfg="cfail3")]
 #[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct AddTypeParameterBound<T: Send>(T);
+struct AddTypeParameterBound<T: Send>(
+    #[rustc_metadata_clean(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    T
+);
 
 
 #[cfg(cfail1)]
@@ -216,7 +265,11 @@ struct AddTypeParameterBoundWhereClause<T>(T);
 #[rustc_clean(label="Hir", cfg="cfail3")]
 #[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
-struct AddTypeParameterBoundWhereClause<T>(T) where T: Sync;
+struct AddTypeParameterBoundWhereClause<T>(
+    #[rustc_metadata_clean(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    T
+) where T: Sync;
 
 
 // Empty struct ----------------------------------------------------------------
@@ -234,6 +287,7 @@ struct Visibility;
 #[cfg(not(cfail1))]
 #[rustc_dirty(label="Hir", cfg="cfail2")]
 #[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
 #[rustc_metadata_clean(cfg="cfail3")]
 pub struct Visibility;
 
@@ -252,9 +306,13 @@ mod tuple_struct_change_field_type_indirectly {
 
     #[rustc_dirty(label="Hir", cfg="cfail2")]
     #[rustc_clean(label="Hir", cfg="cfail3")]
-    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail2")]
     #[rustc_metadata_clean(cfg="cfail3")]
-    struct TupleStruct(FieldType);
+    struct TupleStruct(
+        #[rustc_metadata_dirty(cfg="cfail2")]
+        #[rustc_metadata_clean(cfg="cfail3")]
+        FieldType
+    );
 }
 
 
@@ -267,9 +325,11 @@ mod record_struct_change_field_type_indirectly {
 
     #[rustc_dirty(label="Hir", cfg="cfail2")]
     #[rustc_clean(label="Hir", cfg="cfail3")]
-    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail2")]
     #[rustc_metadata_clean(cfg="cfail3")]
     struct RecordStruct {
+        #[rustc_metadata_dirty(cfg="cfail2")]
+        #[rustc_metadata_clean(cfg="cfail3")]
         _x: FieldType
     }
 }