Define our own assert implementation for the swift compiler sources

For two reasons:
* We also like to check for assert failures in release builds. Although this could be achieved with `precondition`, it's easy to forget about it and use `assert` instead.
* We need to see the error message in crashlogs of release builds. This is even not the case for `precondition`.

Also, re-export the "Basic" module in "SIL" so that the new assert implementation is also available in the Optimizer module (where all files import SIL).

Author: eeckstein

SwiftCompilerSources/Sources/Basic/Utils.swift

@@ -13,6 +13,34 @@
 @_exported import BasicBridging
 import std
 
+/// The assert function to be used in the compiler.
+///
+/// This overrides the standard Swift assert for two reasons:
+/// * We also like to check for assert failures in release builds. Although this could be
+///   achieved with `precondition`, it's easy to forget about it and use `assert` instead.
+/// * We need to see the error message in crashlogs of release builds. This is even not the
+///   case for `precondition`.
+@_transparent
+public func assert(_ condition: Bool, _ message: @autoclosure () -> String,
+                   file: StaticString = #fileID, line: UInt = #line) {
+  if !condition {
+    print("### basic")
+    fatalError(message(), file: file, line: line)
+  }
+}
+
+/// The assert function (without a message) to be used in the compiler.
+///
+/// Unforuntately it's not possible to just add a default argument to `message` in the
+/// other `assert` function. We need to defined this overload.
+@_transparent
+public func assert(_ condition: Bool, file: StaticString = #fileID, line: UInt = #line) {
+  if !condition {
+    fatalError("", file: file, line: line)
+  }
+}
+
+
 //===----------------------------------------------------------------------===//
 //                              StringRef
 //===----------------------------------------------------------------------===//

SwiftCompilerSources/Sources/Optimizer/FunctionPasses/ObjCBridgingOptimization.swift

@@ -10,7 +10,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-import Basic
 import SIL
 
 /// Removes redundant ObjectiveC <-> Swift bridging calls.

SwiftCompilerSources/Sources/Optimizer/InstructionPasses/SimplifyBeginCOWMutation.swift

@@ -10,7 +10,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-import Basic
 import SIL
 
 /// Simplify begin_cow_mutation instructions.

SwiftCompilerSources/Sources/SIL/Utils.swift

@@ -12,6 +12,10 @@
 
 import SILBridging
 
+// Need to export "Basic" to make `Basic.assert` available in the Optimizer module.
+// Otherwise The Optimizer would fall back to Swift's assert implementation.
+@_exported import Basic
+
 //===----------------------------------------------------------------------===//
 //                              Lists
 //===----------------------------------------------------------------------===//