Merge pull request #61887 from nate-chandler/opaque-values/1/20221102

[OpaqueValues] Handle Builtin.addressOfBorrow.

Author: nate-chandler

include/swift/AST/Builtins.def

@@ -915,6 +915,24 @@ BUILTIN_MISC_OPERATION_WITH_SILGEN(EndAsyncLet, "endAsyncLet", "", Special)
 /// until the endAsyncLet.
 BUILTIN_MISC_OPERATION(EndAsyncLetLifetime, "endAsyncLetLifetime", "", Special)
 
+/// addressOfBorrowOpaque (__shared T) -> Builtin.RawPointer
+/// Returns a RawPointer pointing to a borrowed rvalue.  The returned pointer is
+/// only valid within the scope of the borrow.  
+///
+/// Differs from addressOfBorrow only in that it is not lowered until
+/// AddressLowering.
+BUILTIN_MISC_OPERATION(AddressOfBorrowOpaque, "addressOfBorrowOpaque", "", Special)
+
+/// unprotectedAddressOfBorrowOpaque (__shared T) -> Builtin.RawPointer
+/// Returns a RawPointer pointing to a borrowed rvalue. The returned pointer is only
+/// valid within the scope of the borrow.
+/// In contrast to `addressOfBorrowOpaque`, this builtin doesn't trigger an
+/// insertion of stack protectors.
+///
+/// Differs from unprotectedAddressOfBorrow only in that it is not lowered until
+/// AddressLowering.
+BUILTIN_MISC_OPERATION(UnprotectedAddressOfBorrowOpaque, "unprotectedAddressOfBorrowOpaque", "", Special)
+
 /// createAsyncTask(): (
 ///     Int,                            // task-creation flags
 ///     @escaping () async throws -> T  // function

lib/AST/Builtins.cpp

@@ -2701,7 +2701,9 @@ ValueDecl *swift::getBuiltinValueDecl(ASTContext &Context, Identifier Id) {
     return getLegacyCondFailOperation(Context, Id);
 
   case BuiltinValueKind::AddressOfBorrow:
+  case BuiltinValueKind::AddressOfBorrowOpaque:
   case BuiltinValueKind::UnprotectedAddressOfBorrow:
+  case BuiltinValueKind::UnprotectedAddressOfBorrowOpaque:
     if (!Types.empty()) return nullptr;
     return getAddressOfBorrowOperation(Context, Id);
 

lib/SIL/IR/OperandOwnership.cpp

@@ -678,6 +678,8 @@ struct OperandOwnershipBuiltinClassifier
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, ErrorInMain)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, UnexpectedError)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, WillThrow)
+BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, AddressOfBorrowOpaque)
+BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, UnprotectedAddressOfBorrowOpaque)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, AShr)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, GenericAShr)
 BUILTIN_OPERAND_OWNERSHIP(InstantaneousUse, Add)

lib/SIL/IR/ValueOwnership.cpp

@@ -382,6 +382,8 @@ struct ValueOwnershipKindBuiltinVisitor
 // This returns a value at +1 that is destroyed strictly /after/ the
 // UnsafeGuaranteedEnd. This provides the guarantee that we want.
 CONSTANT_OWNERSHIP_BUILTIN(Owned, COWBufferForReading)
+CONSTANT_OWNERSHIP_BUILTIN(None, AddressOfBorrowOpaque)
+CONSTANT_OWNERSHIP_BUILTIN(None, UnprotectedAddressOfBorrowOpaque)
 CONSTANT_OWNERSHIP_BUILTIN(None, AShr)
 CONSTANT_OWNERSHIP_BUILTIN(None, GenericAShr)
 CONSTANT_OWNERSHIP_BUILTIN(None, Add)

lib/SILGen/SILGenBuiltin.cpp

@@ -478,6 +478,17 @@ static ManagedValue emitBuiltinAddressOfBorrowBuiltins(SILGenFunction &SGF,
   // naturally emitted borrowed in memory.
   auto borrow = SGF.emitRValue(argument, SGFContext::AllowGuaranteedPlusZero)
      .getAsSingleValue(SGF, argument);
+  if (!SGF.F.getConventions().useLoweredAddresses()) {
+    auto &context = SGF.getASTContext();
+    auto identifier =
+        stackProtected
+            ? context.getIdentifier("addressOfBorrowOpaque")
+            : context.getIdentifier("unprotectedAddressOfBorrowOpaque");
+    auto builtin = SGF.B.createBuiltin(loc, identifier, rawPointerType,
+                                       substitutions, {borrow.getValue()});
+    return ManagedValue::forUnmanaged(builtin);
+  }
+
   if (!borrow.isPlusZero() || !borrow.getType().isAddress()) {
     SGF.SGM.diagnose(argument->getLoc(), diag::non_borrowed_indirect_addressof);
     return SGF.emitUndef(rawPointerType);

lib/SILOptimizer/Mandatory/AddressLowering.cpp

@@ -2617,13 +2617,29 @@ class UseRewriter : SILInstructionVisitor<UseRewriter> {
     vmi->setOperand(opAddr);
   }
 
+  void visitAddressOfBorrowBuiltinInst(BuiltinInst *bi, bool stackProtected) {
+    SILValue value = bi->getOperand(0);
+    SILValue addr = pass.valueStorageMap.getStorage(value).storageAddress;
+    auto &astCtx = pass.getModule()->getASTContext();
+    SILType rawPointerType = SILType::getRawPointerType(astCtx);
+    SILValue result = builder.createAddressToPointer(
+        bi->getLoc(), addr, rawPointerType, stackProtected);
+    bi->replaceAllUsesWith(result);
+  }
+
   void visitBuiltinInst(BuiltinInst *bi) {
     switch (bi->getBuiltinKind().getValueOr(BuiltinValueKind::None)) {
     case BuiltinValueKind::Copy: {
       SILValue opAddr = addrMat.materializeAddress(use->get());
       bi->setOperand(0, opAddr);
       break;
     }
+    case BuiltinValueKind::AddressOfBorrowOpaque:
+      visitAddressOfBorrowBuiltinInst(bi, /*stackProtected=*/true);
+      break;
+    case BuiltinValueKind::UnprotectedAddressOfBorrowOpaque:
+      visitAddressOfBorrowBuiltinInst(bi, /*stackProtected=*/false);
+      break;
     default:
       bi->dump();
       llvm::report_fatal_error("^^^ Unimplemented builtin opaque value use.");

lib/SILOptimizer/Transforms/AccessEnforcementReleaseSinking.cpp

@@ -193,6 +193,8 @@ static bool isBarrier(SILInstruction *inst) {
     case BuiltinValueKind::ResumeThrowingContinuationThrowing:
     case BuiltinValueKind::AutoDiffProjectTopLevelSubcontext:
     case BuiltinValueKind::AutoDiffAllocateSubcontext:
+    case BuiltinValueKind::AddressOfBorrowOpaque:
+    case BuiltinValueKind::UnprotectedAddressOfBorrowOpaque:
       return true;
     }
   }

test/SILOptimizer/opaque_values_Onone_stdlib.swift

@@ -31,4 +31,22 @@ public func _copy<T>(_ value: T) -> T {
   #endif
 }
 
+// CHECK-LABEL: sil hidden @getRawPointer : {{.*}} {
+// CHECK:       {{bb[0-9]+}}([[ADDR:%[^,]+]] : $*T):
+// CHECK:         [[PTR:%[^,]+]] = address_to_pointer [stack_protection] [[ADDR]]
+// CHECK:         return [[PTR]]
+// CHECK-LABEL: } // end sil function 'getRawPointer'
+@_silgen_name("getRawPointer")
+func getRawPointer<T>(to value: T) -> Builtin.RawPointer {
+  return Builtin.addressOfBorrow(value)
+}
 
+// CHECK-LABEL: sil hidden @getUnprotectedRawPointer : {{.*}} {
+// CHECK:       {{bb[0-9]+}}([[ADDR:%[^,]+]] : $*T):
+// CHECK:         [[PTR:%[^,]+]] = address_to_pointer [[ADDR]]
+// CHECK:         return [[PTR]]
+// CHECK-LABEL: } // end sil function 'getUnprotectedRawPointer'
+@_silgen_name("getUnprotectedRawPointer")
+func getUnprotectedRawPointer<T>(to value: T) -> Builtin.RawPointer {
+  return Builtin.unprotectedAddressOfBorrow(value)
+}