Merge pull request #23660 from DavidGoldman/swift-5.0-branch

Add DebugPrefixMap remapping back to module creation

Author: tkremenek

lib/IRGen/IRGenDebugInfo.cpp

@@ -567,9 +567,11 @@ class IRGenDebugInfoImpl : public IRGenDebugInfo {
     if (Val != DIModuleCache.end())
       return cast<llvm::DIModule>(Val->second);
 
+    std::string RemappedIncludePath = DebugPrefixMap.remapPath(IncludePath);
     StringRef Sysroot = IGM.Context.SearchPathOpts.SDKPath;
     llvm::DIModule *M =
-        DBuilder.createModule(Parent, Name, ConfigMacros, IncludePath, Sysroot);
+        DBuilder.createModule(Parent, Name, ConfigMacros, RemappedIncludePath,
+                              Sysroot);
     DIModuleCache.insert({Key, llvm::TrackingMDNodeRef(M)});
     return M;
   }

test/DebugInfo/debug_prefix_map.swift

@@ -1,7 +1,12 @@
-// RUN: %swiftc_driver -g -debug-prefix-map %S=/var/empty %s -emit-ir -o - | %FileCheck %s
+// RUN: %empty-directory(%t)
+// RUN: %target-swift-frontend -emit-module-path %t/Globals.swiftmodule %S/Globals.swift
+// RUN: %target-swiftc_driver -g -debug-prefix-map %/S=/var/empty -debug-prefix-map %t=/var/empty %/s -I %t -emit-ir -o - | %FileCheck %s
+
+import Globals
 
 func square(_ n: Int) -> Int {
   return n * n
 }
 
 // CHECK: !DIFile(filename: "/var/empty/debug_prefix_map.swift"
+// CHECK: !DIModule(scope: null, name: "Globals", includePath: "/var/empty/Globals.swiftmodule"