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Merged
merged 10 commits into from
Feb 28, 2023
Merged

Generic pointers coerceable #1931

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b6a8e19
gccrs: Fix ICE in ADTType::is_concrete
philberty Feb 26, 2023
a44cf95
gccrs: refactor unify commit as a static function from unify code
philberty Feb 26, 2023
fa9c51a
gccrs: Generic pointers are coerceable
philberty Feb 26, 2023
4ae86b6
gccrs: Allow infer vars on the lhs too
philberty Feb 27, 2023
48c65d2
gccrs: Make coercion sites autoderef cycle optional
philberty Feb 27, 2023
92d3169
gccrs: Only emit errors during type-bounds checking when required
philberty Feb 27, 2023
d5397d9
gccrs: autoderef unconstify so we can use in non const contexts
philberty Feb 27, 2023
5c9a0e4
gccrs: bug-fix implicit inference checks
philberty Feb 27, 2023
27c4590
gccrs: Fix method resolution to use TryCoerce
philberty Feb 27, 2023
ed45b94
gccrs: Remove cmp_autoderef_mode hack from old autoderef
philberty Feb 28, 2023
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8 changes: 4 additions & 4 deletions gcc/rust/backend/rust-compile-base.h
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Expand Up @@ -40,11 +40,11 @@ class HIRCompileBase
protected:
Context *get_context () { return ctx; }

tree coercion_site (HirId id, tree rvalue, const TyTy::BaseType *actual,
const TyTy::BaseType *expected, Location lvalue_locus,
tree coercion_site (HirId id, tree rvalue, TyTy::BaseType *actual,
TyTy::BaseType *expected, Location lvalue_locus,
Location rvalue_locus);
tree coercion_site1 (tree rvalue, const TyTy::BaseType *actual,
const TyTy::BaseType *expected, Location lvalue_locus,
tree coercion_site1 (tree rvalue, TyTy::BaseType *actual,
TyTy::BaseType *expected, Location lvalue_locus,
Location rvalue_locus);

tree coerce_to_dyn_object (tree compiled_ref, const TyTy::BaseType *actual,
Expand Down
9 changes: 4 additions & 5 deletions gcc/rust/backend/rust-compile-expr.cc
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Expand Up @@ -26,7 +26,7 @@
#include "rust-compile-block.h"
#include "rust-compile-implitem.h"
#include "rust-constexpr.h"
#include "rust-unify.h"
#include "rust-type-util.h"
#include "rust-gcc.h"

#include "fold-const.h"
Expand Down Expand Up @@ -2007,10 +2007,9 @@ CompileExpr::resolve_method_address (TyTy::FnType *fntype, HirId ref,
{
TyTy::BaseType *infer_impl_call
= candidate_call->infer_substitions (expr_locus);
monomorphized = Resolver::UnifyRules::Resolve (
TyTy::TyWithLocation (infer_impl_call),
TyTy::TyWithLocation (fntype), expr_locus, true /* commit */,
true /* emit_errors */);
monomorphized
= Resolver::unify_site (ref, TyTy::TyWithLocation (infer_impl_call),
TyTy::TyWithLocation (fntype), expr_locus);
}

return CompileInherentImplItem::Compile (impl_item, ctx, monomorphized);
Expand Down
17 changes: 8 additions & 9 deletions gcc/rust/backend/rust-compile.cc
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Expand Up @@ -54,10 +54,9 @@ CompileCrate::go ()
// Shared methods in compilation

tree
HIRCompileBase::coercion_site (HirId id, tree rvalue,
const TyTy::BaseType *rval,
const TyTy::BaseType *lval,
Location lvalue_locus, Location rvalue_locus)
HIRCompileBase::coercion_site (HirId id, tree rvalue, TyTy::BaseType *rval,
TyTy::BaseType *lval, Location lvalue_locus,
Location rvalue_locus)
{
std::vector<Resolver::Adjustment> *adjustments = nullptr;
bool ok = ctx->get_tyctx ()->lookup_autoderef_mappings (id, &adjustments);
Expand All @@ -70,15 +69,15 @@ HIRCompileBase::coercion_site (HirId id, tree rvalue,
}

tree
HIRCompileBase::coercion_site1 (tree rvalue, const TyTy::BaseType *rval,
const TyTy::BaseType *lval,
Location lvalue_locus, Location rvalue_locus)
HIRCompileBase::coercion_site1 (tree rvalue, TyTy::BaseType *rval,
TyTy::BaseType *lval, Location lvalue_locus,
Location rvalue_locus)
{
if (rvalue == error_mark_node)
return error_mark_node;

const TyTy::BaseType *actual = rval->destructure ();
const TyTy::BaseType *expected = lval->destructure ();
TyTy::BaseType *actual = rval->destructure ();
TyTy::BaseType *expected = lval->destructure ();

if (expected->get_kind () == TyTy::TypeKind::REF)
{
Expand Down
16 changes: 8 additions & 8 deletions gcc/rust/typecheck/rust-autoderef.cc
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Expand Up @@ -26,7 +26,7 @@ namespace Resolver {

static bool
resolve_operator_overload_fn (
Analysis::RustLangItem::ItemType lang_item_type, const TyTy::BaseType *ty,
Analysis::RustLangItem::ItemType lang_item_type, TyTy::BaseType *ty,
TyTy::FnType **resolved_fn, HIR::ImplItem **impl_item,
Adjustment::AdjustmentType *requires_ref_adjustment);

Expand All @@ -40,7 +40,7 @@ Adjuster::adjust_type (const std::vector<Adjustment> &adjustments)
}

Adjustment
Adjuster::try_deref_type (const TyTy::BaseType *ty,
Adjuster::try_deref_type (TyTy::BaseType *ty,
Analysis::RustLangItem::ItemType deref_lang_item)
{
HIR::ImplItem *impl_item = nullptr;
Expand Down Expand Up @@ -85,7 +85,7 @@ Adjuster::try_deref_type (const TyTy::BaseType *ty,
}

Adjustment
Adjuster::try_raw_deref_type (const TyTy::BaseType *ty)
Adjuster::try_raw_deref_type (TyTy::BaseType *ty)
{
bool is_valid_type = ty->get_kind () == TyTy::TypeKind::REF;
if (!is_valid_type)
Expand All @@ -99,7 +99,7 @@ Adjuster::try_raw_deref_type (const TyTy::BaseType *ty)
}

Adjustment
Adjuster::try_unsize_type (const TyTy::BaseType *ty)
Adjuster::try_unsize_type (TyTy::BaseType *ty)
{
bool is_valid_type = ty->get_kind () == TyTy::TypeKind::ARRAY;
if (!is_valid_type)
Expand All @@ -121,7 +121,7 @@ Adjuster::try_unsize_type (const TyTy::BaseType *ty)

static bool
resolve_operator_overload_fn (
Analysis::RustLangItem::ItemType lang_item_type, const TyTy::BaseType *ty,
Analysis::RustLangItem::ItemType lang_item_type, TyTy::BaseType *ty,
TyTy::FnType **resolved_fn, HIR::ImplItem **impl_item,
Adjustment::AdjustmentType *requires_ref_adjustment)
{
Expand Down Expand Up @@ -292,9 +292,9 @@ AutoderefCycle::try_hook (const TyTy::BaseType &)
{}

bool
AutoderefCycle::cycle (const TyTy::BaseType *receiver)
AutoderefCycle::cycle (TyTy::BaseType *receiver)
{
const TyTy::BaseType *r = receiver;
TyTy::BaseType *r = receiver;
while (true)
{
rust_debug ("autoderef try 1: {%s}", r->debug_str ().c_str ());
Expand Down Expand Up @@ -382,7 +382,7 @@ AutoderefCycle::cycle (const TyTy::BaseType *receiver)
}

bool
AutoderefCycle::try_autoderefed (const TyTy::BaseType *r)
AutoderefCycle::try_autoderefed (TyTy::BaseType *r)
{
try_hook (*r);

Expand Down
32 changes: 16 additions & 16 deletions gcc/rust/typecheck/rust-autoderef.h
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Expand Up @@ -40,15 +40,15 @@ class Adjustment
};

// ctor for all adjustments except derefs
Adjustment (AdjustmentType type, const TyTy::BaseType *actual,
const TyTy::BaseType *expected)
Adjustment (AdjustmentType type, TyTy::BaseType *actual,
TyTy::BaseType *expected)
: Adjustment (type, actual, expected, nullptr, nullptr,
AdjustmentType::ERROR)
{}

static Adjustment get_op_overload_deref_adjustment (
AdjustmentType type, const TyTy::BaseType *actual,
const TyTy::BaseType *expected, TyTy::FnType *fn, HIR::ImplItem *deref_item,
AdjustmentType type, TyTy::BaseType *actual, TyTy::BaseType *expected,
TyTy::FnType *fn, HIR::ImplItem *deref_item,
Adjustment::AdjustmentType requires_ref_adjustment)
{
rust_assert (type == DEREF || type == DEREF_MUT);
Expand All @@ -58,8 +58,8 @@ class Adjustment

AdjustmentType get_type () const { return type; }

const TyTy::BaseType *get_actual () const { return actual; }
const TyTy::BaseType *get_expected () const { return expected; }
TyTy::BaseType *get_actual () const { return actual; }
TyTy::BaseType *get_expected () const { return expected; }

std::string as_string () const
{
Expand Down Expand Up @@ -110,8 +110,8 @@ class Adjustment
HIR::ImplItem *get_deref_hir_item () const { return deref_item; }

private:
Adjustment (AdjustmentType type, const TyTy::BaseType *actual,
const TyTy::BaseType *expected, TyTy::FnType *deref_operator_fn,
Adjustment (AdjustmentType type, TyTy::BaseType *actual,
TyTy::BaseType *expected, TyTy::FnType *deref_operator_fn,
HIR::ImplItem *deref_item,
Adjustment::AdjustmentType requires_ref_adjustment)
: type (type), actual (actual), expected (expected),
Expand All @@ -120,8 +120,8 @@ class Adjustment
{}

AdjustmentType type;
const TyTy::BaseType *actual;
const TyTy::BaseType *expected;
TyTy::BaseType *actual;
TyTy::BaseType *expected;

// - only used for deref operator_overloads
//
Expand All @@ -140,12 +140,12 @@ class Adjuster
TyTy::BaseType *adjust_type (const std::vector<Adjustment> &adjustments);

static Adjustment
try_deref_type (const TyTy::BaseType *ty,
try_deref_type (TyTy::BaseType *ty,
Analysis::RustLangItem::ItemType deref_lang_item);

static Adjustment try_raw_deref_type (const TyTy::BaseType *ty);
static Adjustment try_raw_deref_type (TyTy::BaseType *ty);

static Adjustment try_unsize_type (const TyTy::BaseType *ty);
static Adjustment try_unsize_type (TyTy::BaseType *ty);

private:
const TyTy::BaseType *base;
Expand All @@ -158,15 +158,15 @@ class AutoderefCycle

virtual ~AutoderefCycle ();

virtual bool select (const TyTy::BaseType &autoderefed) = 0;
virtual bool select (TyTy::BaseType &autoderefed) = 0;

// optional: this is a chance to hook in to grab predicate items on the raw
// type
virtual void try_hook (const TyTy::BaseType &);

virtual bool cycle (const TyTy::BaseType *receiver);
virtual bool cycle (TyTy::BaseType *receiver);

bool try_autoderefed (const TyTy::BaseType *r);
bool try_autoderefed (TyTy::BaseType *r);

bool autoderef_flag;
std::vector<Adjustment> adjustments;
Expand Down
3 changes: 2 additions & 1 deletion gcc/rust/typecheck/rust-casts.cc
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Expand Up @@ -39,7 +39,8 @@ TypeCastRules::check ()
{
// https://github.com/rust-lang/rust/blob/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/compiler/rustc_typeck/src/check/cast.rs#L565-L582
auto possible_coercion
= TypeCoercionRules::TryCoerce (from.get_ty (), to.get_ty (), locus);
= TypeCoercionRules::TryCoerce (from.get_ty (), to.get_ty (), locus,
true /*allow-autoderef*/);
if (!possible_coercion.is_error ())
return possible_coercion;

Expand Down
81 changes: 64 additions & 17 deletions gcc/rust/typecheck/rust-coercion.cc
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Expand Up @@ -18,34 +18,37 @@

#include "rust-hir-type-check-base.h"
#include "rust-coercion.h"
#include "rust-unify.h"
#include "rust-type-util.h"

namespace Rust {
namespace Resolver {

TypeCoercionRules::CoercionResult
TypeCoercionRules::Coerce (TyTy::BaseType *receiver, TyTy::BaseType *expected,
Location locus)
Location locus, bool allow_autoderef)
{
TypeCoercionRules resolver (expected, locus, true);
TypeCoercionRules resolver (expected, locus, true, allow_autoderef, false);
bool ok = resolver.do_coercion (receiver);
return ok ? resolver.try_result : CoercionResult::get_error ();
}

TypeCoercionRules::CoercionResult
TypeCoercionRules::TryCoerce (TyTy::BaseType *receiver,
TyTy::BaseType *expected, Location locus)
TyTy::BaseType *expected, Location locus,
bool allow_autoderef)
{
TypeCoercionRules resolver (expected, locus, false);
TypeCoercionRules resolver (expected, locus, false, allow_autoderef, true);
bool ok = resolver.do_coercion (receiver);
return ok ? resolver.try_result : CoercionResult::get_error ();
}

TypeCoercionRules::TypeCoercionRules (TyTy::BaseType *expected, Location locus,
bool emit_errors)
: AutoderefCycle (false), mappings (Analysis::Mappings::get ()),
bool emit_errors, bool allow_autoderef,
bool try_flag)
: AutoderefCycle (!allow_autoderef), mappings (Analysis::Mappings::get ()),
context (TypeCheckContext::get ()), expected (expected), locus (locus),
try_result (CoercionResult::get_error ()), emit_errors (emit_errors)
try_result (CoercionResult::get_error ()), emit_errors (emit_errors),
try_flag (try_flag)
{}

bool
Expand Down Expand Up @@ -138,6 +141,31 @@ TypeCoercionRules::do_coercion (TyTy::BaseType *receiver)
break;
}

// https://github.com/rust-lang/rust/blob/7eac88abb2e57e752f3302f02be5f3ce3d7adfb4/compiler/rustc_typeck/src/check/coercion.rs#L210
switch (receiver->get_kind ())
{
default: {
rust_debug (
"do_coercion default unify and infer expected: %s receiver %s",
receiver->debug_str ().c_str (), expected->debug_str ().c_str ());
TyTy::BaseType *result
= unify_site_and (receiver->get_ref (),
TyTy::TyWithLocation (expected),
TyTy::TyWithLocation (receiver),
locus /*unify_locus*/, false /*emit_errors*/,
!try_flag /*commit_if_ok*/, true /*infer*/,
try_flag /*cleanup on error*/);
rust_debug ("result");
result->debug ();
if (result->get_kind () != TyTy::TypeKind::ERROR)
{
try_result = CoercionResult{{}, result};
return true;
}
}
break;
}

return !try_result.is_error ();
}

Expand All @@ -146,7 +174,7 @@ TypeCoercionRules::coerce_unsafe_ptr (TyTy::BaseType *receiver,
TyTy::PointerType *expected,
Mutability to_mutbl)
{
rust_debug ("coerce_unsafe_ptr(a={%s}, b={%s})",
rust_debug ("coerce_unsafe_ptr(receiver={%s}, expected={%s})",
receiver->debug_str ().c_str (), expected->debug_str ().c_str ());

Mutability from_mutbl = Mutability::Imm;
Expand All @@ -169,13 +197,21 @@ TypeCoercionRules::coerce_unsafe_ptr (TyTy::BaseType *receiver,
break;

default: {
// FIXME this can probably turn into a unify_and
if (receiver->can_eq (expected, false))
return CoercionResult{{}, expected->clone ()};

return CoercionResult::get_error ();
}
}

bool receiver_is_non_ptr = receiver->get_kind () != TyTy::TypeKind::POINTER;
if (autoderef_flag && receiver_is_non_ptr)
{
// it is unsafe to autoderef to raw pointers
return CoercionResult::get_error ();
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Unsafe as in "this is allowed in unsafe contexts"? Or is it always forbidden?

}

if (!coerceable_mutability (from_mutbl, to_mutbl))
{
Location lhs = mappings->lookup_location (receiver->get_ref ());
Expand All @@ -184,13 +220,21 @@ TypeCoercionRules::coerce_unsafe_ptr (TyTy::BaseType *receiver,
return TypeCoercionRules::CoercionResult::get_error ();
}

TyTy::PointerType *result
TyTy::PointerType *coerced_mutability
= new TyTy::PointerType (receiver->get_ref (),
TyTy::TyVar (element->get_ref ()), to_mutbl);
if (!result->can_eq (expected, false))
return CoercionResult::get_error ();

return CoercionResult{{}, result};
TyTy::BaseType *result
= unify_site_and (receiver->get_ref (), TyTy::TyWithLocation (expected),
TyTy::TyWithLocation (coerced_mutability),
locus /*unify_locus*/, false /*emit_errors*/,
!try_flag /*commit_if_ok*/, true /*infer*/,
try_flag /*cleanup on error*/);
bool unsafe_ptr_coerceion_ok = result->get_kind () != TyTy::TypeKind::ERROR;
if (unsafe_ptr_coerceion_ok)
return CoercionResult{{}, result};

return TypeCoercionRules::CoercionResult::get_error ();
}

/// Reborrows `&mut A` to `&mut B` and `&(mut) A` to `&B`.
Expand Down Expand Up @@ -220,9 +264,12 @@ TypeCoercionRules::coerce_borrowed_pointer (TyTy::BaseType *receiver,
// back to a final unity anyway
rust_debug ("coerce_borrowed_pointer -- unify");
TyTy::BaseType *result
= UnifyRules::Resolve (TyTy::TyWithLocation (receiver),
TyTy::TyWithLocation (expected), locus,
true /* commit */, true /* emit_errors */);
= unify_site_and (receiver->get_ref (),
TyTy::TyWithLocation (receiver),
TyTy::TyWithLocation (expected), locus,
false /*emit_errors*/, true /*commit_if_ok*/,
false /* FIXME infer do we want to allow this?? */,
true /*cleanup_on_failure*/);
return CoercionResult{{}, result};
}
}
Expand Down Expand Up @@ -365,7 +412,7 @@ TypeCoercionRules::coerce_unsized (TyTy::BaseType *source,
}

bool
TypeCoercionRules::select (const TyTy::BaseType &autoderefed)
TypeCoercionRules::select (TyTy::BaseType &autoderefed)
{
rust_debug (
"autoderef type-coercion select autoderefed={%s} can_eq expected={%s}",
Expand Down
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