| // RUN: %target-swift-frontend -c %s -g -O -parse-stdlib -parse-as-library -module-name Swift |
| |
| // TF-597: Exact minimal reproducer for IRGenDebugInfo crash. |
| // Crash occurred only with `-g` and `-O`. |
| // |
| // ``` |
| // Assertion failed: (OffsetInBits + SizeInBits <= getSizeInBits(Var) && "pars > totum"), |
| // function emitVariableDeclaration, file swift/lib/IRGen/IRGenDebugInfo.cpp, line 2216. |
| // Stack dump: |
| // 1. Swift version 5.1-dev (LLVM 200186e28b, Swift c09c14dec5) |
| // 2. While emitting IR SIL function "@$ss8pullback2at2inyx_q_xXFts14DifferentiableRzsADR_r0_lF". |
| // for 'pullback(at:in:)' (at swift/test/AutoDiff/differentiable_func_debuginfo.swift:21:8) |
| // ``` |
| // |
| // The crash was because `IRGenDebugInfoImpl::getOrCreateType` computes |
| // `llvm::DIType` type debug info by demangling type names. |
| // |
| // Since `@differentiable` and `@differentiable(linear)` function types did |
| // not have mangling support, `getOrCreateType` computed a regular `(A) -> B` |
| // function type instead of a `@differentiable (A) -> B` function type, leading |
| // to a type size inconsistency. |
| // |
| // Conclusion: mangling coverage is important. |
| |
| // Minimal dummy compiler-known `Differentiable` protocol. |
| public protocol Differentiable { |
| associatedtype TangentVector |
| } |
| |
| // This declaration is necessary to reproduce the crash. |
| // `Builtin.autodiffApply_vjp` constructs a use of the `tf597ProblematicVarDecl` |
| // type, which was mangled without `@differentiable` attribute. The parameter |
| // for `blackHole` is of type `$@noescape @callee_guaranteed (@in_guaranteed T) -> @out U`, |
| // which matched the mangled name for the type of the parameter of `blackHole`. |
| // As a result, the types are uniqued when generating debug info. The type of |
| // the parameter of `blackHole` is smaller than the `@differentiable` function |
| // type, causing IRGenDebugInfo to crash. |
| public func blackHole<T, U>(_: (T) -> U) {} |
| |
| public func pullback<T, R>( |
| at x: T, in tf597ProblematicVarDecl: @differentiable (T) -> R |
| ) { |
| let _ = Builtin.applyDerivative_vjp(tf597ProblematicVarDecl, x) |
| } |
