Merge #1090 #1097 #1098 #1099 #1101

1090: macros: add concat! macro r=philberty a=liushuyu

- extracts parenthesis-matching logic into a function
- adds `concat!` macro

1097: Support mangling *const ptr and slices like *const [T] r=philberty a=philberty

The legacy mangling scheme needs to convert the canonical path containing
* for pointers and the [] brackets representing slices into:

  * = $BP$
  [ = $u5b$
  ] = $u5d$

These symbols are not allowed in asm symbols.

Addresses #849


1098: Ensure unsize method resolutions actually unsize r=philberty a=philberty

This was a typo when unsized method resolution was added, where the
adjustment was wrongly marked as an indirection. The enum is required so
that the code generation adjustment takes place.

Addresses #849

1099: Fix bad inherent overlap error r=philberty a=philberty

When we examine HIR::ImplBlock's we determine if an impl might overlap
another impl based on the Self type. So for example you might have a
generic structure Foo<T>(T), and an associated impl block for Foo<i32>, but
then go on to define an associated impl of Foo<T> the generic one will
overlap any associated impl hiding the generic implementation.

In this case we have two generic impl blocks

  *const [T]
  *const T

This means the *const T might overlap with the slice one since it is
generic. As bjorn3 pointed out in #1075 , the correct implementation is to
observe that [T] is constrained by size but untill we have the auto trait
of Sized we must example the two generic impls and just determine that
they are not-equal so for now this is the best implementation we can do.

Fixes #1075 


1101: Add helper as_string for DefIds r=philberty a=philberty

This just adds a useful helper to as_string DefId's directly

Co-authored-by: liushuyu <liushuyu011@gmail.com>
Co-authored-by: Philip Herron <philip.herron@embecosm.com>

gcc/rust/backend/rust-mangle.cc

@@ -11,6 +11,9 @@ static const std::string kMangledSubstBegin = "$LT$";
 static const std::string kMangledSubstEnd = "$GT$";
 static const std::string kMangledSpace = "$u20$";
 static const std::string kMangledRef = "$RF$";
+static const std::string kMangledPtr = "$BP$";
+static const std::string kMangledLeftSqParen = "$u5b$";	 // [
+static const std::string kMangledRightSqParen = "$u5d$"; // ]
 static const std::string kQualPathBegin = "_" + kMangledSubstBegin;
 
 namespace Rust {
@@ -29,8 +32,15 @@ legacy_mangle_name (const std::string &name)
   // <example::Bar as example::A>::fooA:
   // _ZN43_$LT$example..Bar$u20$as$u20$example..A$GT$4fooA17hfc615fa76c7db7a0E:
   //
+  // core::ptr::const_ptr::<impl *const T>::cast:
+  // _ZN4core3ptr9const_ptr33_$LT$impl$u20$$BP$const$u20$T$GT$4cast17hb79f4617226f1d55E:
+  //
+  // core::ptr::const_ptr::<impl *const [T]>::as_ptr:
+  // _ZN4core3ptr9const_ptr43_$LT$impl$u20$$BP$const$u20$$u5b$T$u5d$$GT$6as_ptr17he16e0dcd9473b04fE:
+  //
   // example::Foo<T>::new:
   // _ZN7example12Foo$LT$T$GT$3new17h9a2aacb7fd783515E:
+
   std::string buffer;
   for (size_t i = 0; i < name.size (); i++)
     {
@@ -47,6 +57,12 @@ legacy_mangle_name (const std::string &name)
 	m = kMangledSubstBegin;
       else if (c == '>')
 	m = kMangledSubstEnd;
+      else if (c == '*')
+	m = kMangledPtr;
+      else if (c == '[')
+	m = kMangledLeftSqParen;
+      else if (c == ']')
+	m = kMangledRightSqParen;
       else if (c == ':')
 	{
 	  rust_assert (i + 1 < name.size ());

gcc/rust/expand/rust-macro-builtins.cc

@@ -34,17 +34,12 @@ make_string (Location locus, std::string value)
 			  PrimitiveCoreType::CORETYPE_STR, {}, locus));
 }
 
-/* Parse a single string literal from the given delimited token tree,
-   and return the LiteralExpr for it. Allow for an optional trailing comma,
-   but otherwise enforce that these are the only tokens.  */
+/* Match the end token of a macro given the start delimiter of the macro */
 
-std::unique_ptr<AST::LiteralExpr>
-parse_single_string_literal (AST::DelimTokenTree &invoc_token_tree,
-			     Location invoc_locus)
+static inline TokenId
+macro_end_token (AST::DelimTokenTree &invoc_token_tree,
+		 Parser<MacroInvocLexer> &parser)
 {
-  MacroInvocLexer lex (invoc_token_tree.to_token_stream ());
-  Parser<MacroInvocLexer> parser (std::move (lex));
-
   auto last_token_id = TokenId::RIGHT_CURLY;
   switch (invoc_token_tree.get_delim_type ())
     {
@@ -63,6 +58,22 @@ parse_single_string_literal (AST::DelimTokenTree &invoc_token_tree,
       break;
     }
 
+  return last_token_id;
+}
+
+/* Parse a single string literal from the given delimited token tree,
+   and return the LiteralExpr for it. Allow for an optional trailing comma,
+   but otherwise enforce that these are the only tokens.  */
+
+std::unique_ptr<AST::LiteralExpr>
+parse_single_string_literal (AST::DelimTokenTree &invoc_token_tree,
+			     Location invoc_locus)
+{
+  MacroInvocLexer lex (invoc_token_tree.to_token_stream ());
+  Parser<MacroInvocLexer> parser (std::move (lex));
+
+  auto last_token_id = macro_end_token (invoc_token_tree, parser);
+
   std::unique_ptr<AST::LiteralExpr> lit_expr = nullptr;
 
   if (parser.peek_current_token ()->get_id () == STRING_LITERAL)
@@ -252,4 +263,44 @@ MacroBuiltin::compile_error (Location invoc_locus, AST::MacroInvocData &invoc)
   return AST::ASTFragment::create_error ();
 }
 
+/* Expand builtin macro concat!(), which joins all the literal parameters
+   into a string with no delimiter. */
+
+AST::ASTFragment
+MacroBuiltin::concat (Location invoc_locus, AST::MacroInvocData &invoc)
+{
+  auto invoc_token_tree = invoc.get_delim_tok_tree ();
+  MacroInvocLexer lex (invoc_token_tree.to_token_stream ());
+  Parser<MacroInvocLexer> parser (std::move (lex));
+  auto str = std::string ();
+  bool has_error = false;
+
+  auto last_token_id = macro_end_token (invoc_token_tree, parser);
+
+  /* NOTE: concat! could accept no argument, so we don't have any checks here */
+  while (parser.peek_current_token ()->get_id () != last_token_id)
+    {
+      auto lit_expr = parser.parse_literal_expr ();
+      if (lit_expr)
+	{
+	  str += lit_expr->as_string ();
+	}
+      else
+	{
+	  rust_error_at (parser.peek_current_token ()->get_locus (),
+			 "argument must be a constant literal");
+	  has_error = true;
+	}
+      parser.maybe_skip_token (COMMA);
+    }
+
+  parser.skip_token (last_token_id);
+
+  if (has_error)
+    return AST::ASTFragment::create_error ();
+
+  auto node = AST::SingleASTNode (make_string (invoc_locus, str));
+  return AST::ASTFragment ({node});
+}
+
 } // namespace Rust

gcc/rust/expand/rust-macro-builtins.h

@@ -80,6 +80,9 @@ public:
 
   static AST::ASTFragment compile_error (Location invoc_locus,
 					 AST::MacroInvocData &invoc);
+
+  static AST::ASTFragment concat (Location invoc_locus,
+				  AST::MacroInvocData &invoc);
 };
 } // namespace Rust
 

gcc/rust/typecheck/rust-autoderef.cc

@@ -116,7 +116,7 @@ Adjuster::try_unsize_type (const TyTy::BaseType *ty)
 			   TyTy::TyVar (slice_elem->get_ref ()));
   context->insert_implicit_type (slice);
 
-  return Adjustment (Adjustment::AdjustmentType::INDIRECTION, slice);
+  return Adjustment (Adjustment::AdjustmentType::UNSIZE, slice);
 }
 
 static bool

gcc/rust/typecheck/rust-hir-inherent-impl-overlap.h

@@ -123,7 +123,26 @@ public:
 	      continue;
 
 	    if (query->can_eq (candidate, false))
-	      possible_collision (it->second, iy->second);
+	      {
+		// we might be in the case that we have:
+		//
+		// *const T vs *const [T]
+		//
+		// so lets use an equality check when the
+		// candidates are both generic to be sure we dont emit a false
+		// positive
+
+		bool a = query->is_concrete ();
+		bool b = candidate->is_concrete ();
+		bool both_generic = !a && !b;
+		if (both_generic)
+		  {
+		    if (!query->is_equal (*candidate))
+		      continue;
+		  }
+
+		possible_collision (it->second, iy->second);
+	      }
 	  }
       }
   }
@@ -152,8 +171,8 @@ public:
   void collision_detected (HIR::ImplItem *query, HIR::ImplItem *dup,
 			   const std::string &name)
   {
-    RichLocation r (query->get_locus ());
-    r.add_range (dup->get_locus ());
+    RichLocation r (dup->get_locus ());
+    r.add_range (query->get_locus ());
     rust_error_at (r, "duplicate definitions with name %s", name.c_str ());
   }
 

gcc/rust/typecheck/rust-hir-path-probe.h

@@ -284,7 +284,10 @@ protected:
       return;
 
     if (!receiver->can_eq (impl_block_ty, false))
-      return;
+      {
+	if (!impl_block_ty->can_eq (receiver, false))
+	  return;
+      }
 
     // lets visit the impl_item
     item->accept_vis (*this);

gcc/rust/typecheck/rust-tyty-bounds.cc

@@ -41,7 +41,10 @@ TypeBoundsProbe::scan ()
 	return true;
 
       if (!receiver->can_eq (impl_type, false))
-	return true;
+	{
+	  if (!impl_type->can_eq (receiver, false))
+	    return true;
+	}
 
       possible_trait_paths.push_back ({impl->get_trait_ref ().get (), impl});
       return true;

gcc/rust/typecheck/rust-tyty-cmp.h

@@ -886,8 +886,6 @@ public:
     ok = true;
   }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const ArrayType *base;
@@ -916,8 +914,6 @@ public:
     ok = true;
   }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const SliceType *base;
@@ -939,8 +935,6 @@ public:
     ok = type.get_infer_kind () == InferType::InferTypeKind::GENERAL;
   }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const BoolType *base;
@@ -965,8 +959,6 @@ public:
     ok = type.get_int_kind () == base->get_int_kind ();
   }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const IntType *base;
@@ -991,8 +983,6 @@ public:
     ok = type.get_uint_kind () == base->get_uint_kind ();
   }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const UintType *base;
@@ -1017,8 +1007,6 @@ public:
     ok = type.get_float_kind () == base->get_float_kind ();
   }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const FloatType *base;
@@ -1120,8 +1108,6 @@ public:
     ok = true;
   }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const TupleType *base;
@@ -1143,8 +1129,6 @@ public:
 
   void visit (const USizeType &type) override { ok = true; }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const USizeType *base;
@@ -1166,8 +1150,6 @@ public:
 
   void visit (const ISizeType &type) override { ok = true; }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const ISizeType *base;
@@ -1189,8 +1171,6 @@ public:
 
   void visit (const CharType &type) override { ok = true; }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const CharType *base;
@@ -1365,8 +1345,6 @@ public:
 
   void visit (const StrType &type) override { ok = true; }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const StrType *base;
@@ -1383,8 +1361,6 @@ public:
 
   void visit (const NeverType &type) override { ok = true; }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
   const NeverType *base;
@@ -1478,8 +1454,6 @@ public:
     ok = base->bounds_compatible (type, ref_locus, false);
   }
 
-  void visit (const ParamType &type) override { ok = true; }
-
 private:
   const BaseType *get_base () const override { return base; }
 

gcc/rust/util/rust-hir-map.cc

@@ -754,6 +754,7 @@ Mappings::insert_macro_def (AST::MacroRulesDefinition *macro)
       {"include_bytes", MacroBuiltin::include_bytes},
       {"include_str", MacroBuiltin::include_str},
       {"compile_error", MacroBuiltin::compile_error},
+      {"concat", MacroBuiltin::concat},
     };
 
   auto builtin = builtin_macros.find (macro->get_rule_name ());

gcc/rust/util/rust-mapping-common.h

@@ -50,6 +50,15 @@ struct DefId
     return ((uint64_t) this->crateNum << 32 | this->localDefId)
 	   < ((uint64_t) other.crateNum << 32 | other.localDefId);
   }
+
+  std::string as_string () const
+  {
+    std::string buf;
+    buf += std::to_string (crateNum);
+    buf += " "; // or anything else
+    buf += std::to_string (localDefId);
+    return buf;
+  }
 };
 
 #define UNKNOWN_CREATENUM ((uint32_t) (0))

gcc/testsuite/rust/compile/builtin_macro_concat.rs

@@ -0,0 +1,15 @@
+macro_rules! concat {
+  () => {{}};
+}
+
+fn main () {
+  let not_literal = "identifier";
+  concat! ();
+  concat! (,); // { dg-error "argument must be a constant literal" }
+  concat! (not_literal); // { dg-error "argument must be a constant literal" }
+  concat! ("message");
+  concat! ("message",);
+  concat! ("message",1, true, false, 1.0, 10usize, 2000u64);
+  concat! ("message",1, true, false, 1.0, 10usize, 2000u64,);
+  concat! ("m", not_literal); // { dg-error "argument must be a constant literal" }
+}

gcc/testsuite/rust/compile/generics7.rs

@@ -15,7 +15,7 @@ impl Foo<char> {
 }
 
 impl<T> Foo<T> {
-    fn bar(self) -> T { // { dg-error "duplicate definitions with name bar" }
+    fn bar(self) -> T {
         self.a
     }
 }

gcc/testsuite/rust/compile/generics8.rs

@@ -1,7 +1,7 @@
 struct Foo<A, B>(A, B);
 
 impl<T> Foo<i32, T> {
-    fn test(a: T) -> T { // { dg-error "duplicate definitions with name test" }
+    fn test(a: T) -> T {
         a
     }
 }

gcc/testsuite/rust/compile/torture/issue-1075.rs

@@ -0,0 +1,42 @@
+// { dg-additional-options "-w" }
+extern "rust-intrinsic" {
+    pub fn offset<T>(dst: *const T, offset: isize) -> *const T;
+}
+
+struct FatPtr<T> {
+    data: *const T,
+    len: usize,
+}
+
+union Repr<T> {
+    rust: *const [T],
+    rust_mut: *mut [T],
+    raw: FatPtr<T>,
+}
+
+impl<T> *const [T] {
+    pub const fn len(self) -> usize {
+        // SAFETY: this is safe because `*const [T]` and `FatPtr<T>` have the same layout.
+        // Only `std` can make this guarantee.
+        let a = unsafe { Repr { rust: self }.raw };
+        a.len
+    }
+
+    pub const fn as_ptr(self) -> *const T {
+        self as *const T
+    }
+}
+
+impl<T> *const T {
+    pub const unsafe fn offset(self, count: isize) -> *const T {
+        unsafe { offset(self, count) }
+    }
+
+    pub const unsafe fn add(self, count: usize) -> Self {
+        unsafe { self.offset(count as isize) }
+    }
+
+    pub const fn as_ptr(self) -> *const T {
+        self as *const T
+    }
+}

gcc/testsuite/rust/execute/torture/builtin_macro_concat.rs

@@ -0,0 +1,23 @@
+// { dg-output "\ntest10btrue2.15\ntest10bfalse2.151\n" }
+macro_rules! concat {
+    () => {{}};
+}
+
+extern "C" {
+    fn printf(fmt: *const i8, ...);
+}
+
+fn print(s: &str) {
+    printf("%s\n" as *const str as *const i8, s as *const str as *const i8);
+}
+
+fn main() -> i32 {
+    let a = concat!();
+    let b = concat!("test", 10, 'b', true, 2.15);
+    let c = concat!("test", 10, 'b', false, 2.15, 1u64);
+    print(a);
+    print(b);
+    print(c);
+
+    0
+}