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[IRGen] Always load extra tag bits as full bytes in CVW to avoid elem… #74952

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Merged
merged 1 commit into from
Jul 3, 2024
Merged

[IRGen] Always load extra tag bits as full bytes in CVW to avoid elem… #74952

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15 changes: 13 additions & 2 deletions lib/IRGen/GenEnum.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1688,11 +1688,22 @@ namespace {
auto payload = EnumPayload::load(IGF, projectPayload(IGF, addr),
PayloadSchema);
if (ExtraTagBitCount > 0) {
extraTag = IGF.Builder.CreateLoad(projectExtraTagBits(IGF, addr));
if (maskExtraTagBits) {
auto maskBits = llvm::NextPowerOf2(NumExtraTagValues) - 1;
auto projectedBits = projectExtraTagBits(IGF, addr);
// LLVM assumes that loads of fractional byte sizes have been stored
// with the same type, so all unused bits would be 0. Since we are
// re-using spare bits for tag storage, that assumption is wrong here.
// In CVW we have to mask the extra bits, which requires us to make
// this cast here, otherwise LLVM would optimize away the bit mask.
if (projectedBits.getElementType()->getIntegerBitWidth() < 8) {
projectedBits = IGF.Builder.CreateElementBitCast(addr, IGM.Int8Ty);
}
extraTag = IGF.Builder.CreateLoad(projectedBits);
auto maskBits = llvm::PowerOf2Ceil(NumExtraTagValues) - 1;
auto mask = llvm::ConstantInt::get(extraTag->getType(), maskBits);
extraTag = IGF.Builder.CreateAnd(extraTag, mask);
} else {
extraTag = IGF.Builder.CreateLoad(projectExtraTagBits(IGF, addr));
}
}
return {std::move(payload), extraTag};
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10 changes: 10 additions & 0 deletions test/Interpreter/Inputs/layout_string_witnesses_types.swift
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Expand Up @@ -619,6 +619,16 @@ public enum MultiPayloadError {
case error2(Int, Error)
}

public enum TwoPayloadInner {
case x(AnyObject)
case y(Int)
}

public enum TwoPayloadOuter {
case x(Int)
case y(TwoPayloadInner)
}

@inline(never)
public func consume<T>(_ x: T.Type) {
withExtendedLifetime(x) {}
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39 changes: 34 additions & 5 deletions test/Interpreter/layout_string_witnesses_static.swift
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@@ -1,12 +1,12 @@
// RUN: %empty-directory(%t)
// RUN: %target-swift-frontend -I %S/Inputs/CTypes -enable-experimental-feature LayoutStringValueWitnesses -enable-layout-string-value-witnesses -parse-stdlib -emit-module -emit-module-path=%t/layout_string_witnesses_types.swiftmodule %S/Inputs/layout_string_witnesses_types.swift
// RUN: %target-swift-frontend -O -I %S/Inputs/CTypes -enable-experimental-feature LayoutStringValueWitnesses -enable-layout-string-value-witnesses -parse-stdlib -emit-module -emit-module-path=%t/layout_string_witnesses_types.swiftmodule %S/Inputs/layout_string_witnesses_types.swift

// NOTE: We have to build this as dylib to turn private external symbols into local symbols, so we can observe potential issues with linkage
// RUN: %target-build-swift-dylib(%t/%target-library-name(layout_string_witnesses_types)) -I %S/Inputs/CTypes -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnesses -Xfrontend -enable-layout-string-value-witnesses -Xfrontend -parse-stdlib -parse-as-library %S/Inputs/layout_string_witnesses_types.swift
// RUN: %target-build-swift-dylib(%t/%target-library-name(layout_string_witnesses_types)) -O -I %S/Inputs/CTypes -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnesses -Xfrontend -enable-layout-string-value-witnesses -Xfrontend -parse-stdlib -parse-as-library %S/Inputs/layout_string_witnesses_types.swift
// RUN: %target-codesign %t/%target-library-name(layout_string_witnesses_types)
// RUN: %target-swift-frontend -enable-experimental-feature LayoutStringValueWitnesses -enable-layout-string-value-witnesses -enable-library-evolution -emit-module -emit-module-path=%t/layout_string_witnesses_types_resilient.swiftmodule %S/Inputs/layout_string_witnesses_types_resilient.swift
// RUN: %target-build-swift -g -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnesses -Xfrontend -enable-layout-string-value-witnesses -Xfrontend -enable-library-evolution -c -parse-as-library -o %t/layout_string_witnesses_types_resilient.o %S/Inputs/layout_string_witnesses_types_resilient.swift
// RUN: %target-build-swift -g -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnesses -Xfrontend -enable-layout-string-value-witnesses -Xfrontend -enable-type-layout -Xfrontend -parse-stdlib -module-name layout_string_witnesses_static -llayout_string_witnesses_types -L%t %t/layout_string_witnesses_types_resilient.o -I %t -o %t/main %s %target-rpath(%t)
// RUN: %target-swift-frontend -O -enable-experimental-feature LayoutStringValueWitnesses -enable-layout-string-value-witnesses -enable-library-evolution -emit-module -emit-module-path=%t/layout_string_witnesses_types_resilient.swiftmodule %S/Inputs/layout_string_witnesses_types_resilient.swift
// RUN: %target-build-swift -O -g -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnesses -Xfrontend -enable-layout-string-value-witnesses -Xfrontend -enable-library-evolution -c -parse-as-library -o %t/layout_string_witnesses_types_resilient.o %S/Inputs/layout_string_witnesses_types_resilient.swift
// RUN: %target-build-swift -O -g -Xfrontend -enable-experimental-feature -Xfrontend LayoutStringValueWitnesses -Xfrontend -enable-layout-string-value-witnesses -Xfrontend -enable-type-layout -Xfrontend -parse-stdlib -module-name layout_string_witnesses_static -llayout_string_witnesses_types -L%t %t/layout_string_witnesses_types_resilient.o -I %t -o %t/main %s %target-rpath(%t)
// RUN: %target-codesign %t/main
// RUN: %target-run %t/main %t/%target-library-name(layout_string_witnesses_types) | %FileCheck %s --check-prefix=CHECK -check-prefix=CHECK-%target-os

Expand Down Expand Up @@ -1290,6 +1290,35 @@ func testCTypeUnderAligned() {

testCTypeUnderAligned()

func testNestedTwoPayload() {
let ptr = UnsafeMutablePointer<TwoPayloadOuter>.allocate(capacity: 1)

do {
let x = TwoPayloadOuter.y(TwoPayloadInner.x(SimpleClass(x: 23)))
testInit(ptr, to: x)
}

do {
let y = TwoPayloadOuter.y(TwoPayloadInner.x(SimpleClass(x: 1)))

// CHECK: Before deinit
print("Before deinit")

// CHECK-NEXT: SimpleClass deinitialized!
testAssign(ptr, from: y)
}

// CHECK-NEXT: Before deinit
print("Before deinit")

// CHECK-NEXT: SimpleClass deinitialized!
testDestroy(ptr)

ptr.deallocate()
}

testNestedTwoPayload()

#if os(macOS)
func testObjc() {
let ptr = UnsafeMutablePointer<ObjcWrapper>.allocate(capacity: 1)
Expand Down