Revert "Avoid emitting redundant or unusable directories in DIFile metadata entries."

This reverts commit r348154 and follow-up commits r348211 and r3248213.
Reason: the original commit broke compiler-rt tests and a follow-up fix
(r348203) broke our integrate and was reverted.

llvm-svn: 348280

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -181,7 +181,8 @@ void CGDebugInfo::setLocation(SourceLocation Loc) {
   SourceManager &SM = CGM.getContext().getSourceManager();
   auto *Scope = cast<llvm::DIScope>(LexicalBlockStack.back());
   PresumedLoc PCLoc = SM.getPresumedLoc(CurLoc);
-  if (PCLoc.isInvalid() || Scope->getFile() == getOrCreateFile(CurLoc))
+
+  if (PCLoc.isInvalid() || Scope->getFilename() == PCLoc.getFilename())
     return;
 
   if (auto *LBF = dyn_cast<llvm::DILexicalBlockFile>(Scope)) {
@@ -409,13 +410,13 @@ llvm::DIFile *CGDebugInfo::getOrCreateFile(SourceLocation Loc) {
   SourceManager &SM = CGM.getContext().getSourceManager();
   PresumedLoc PLoc = SM.getPresumedLoc(Loc);
 
-  StringRef FileName = PLoc.getFilename();
-  if (PLoc.isInvalid() || FileName.empty())
+  if (PLoc.isInvalid() || StringRef(PLoc.getFilename()).empty())
     // If the location is not valid then use main input file.
     return getOrCreateMainFile();
 
   // Cache the results.
-  auto It = DIFileCache.find(FileName.data());
+  const char *fname = PLoc.getFilename();
+  auto It = DIFileCache.find(fname);
 
   if (It != DIFileCache.end()) {
     // Verify that the information still exists.
@@ -430,41 +431,11 @@ llvm::DIFile *CGDebugInfo::getOrCreateFile(SourceLocation Loc) {
   if (CSKind)
     CSInfo.emplace(*CSKind, Checksum);
 
-  StringRef Dir;
-  StringRef File;
-  std::string RemappedFile = remapDIPath(FileName);
-  std::string CurDir = remapDIPath(getCurrentDirname());
-  SmallString<128> DirBuf;
-  SmallString<128> FileBuf;
-  if (llvm::sys::path::is_absolute(RemappedFile)) {
-    // Strip the common prefix (if it is more than just "/") from current
-    // directory and FileName for a more space-efficient encoding.
-    auto FileIt = llvm::sys::path::begin(RemappedFile);
-    auto FileE = llvm::sys::path::end(RemappedFile);
-    auto CurDirIt = llvm::sys::path::begin(CurDir);
-    auto CurDirE = llvm::sys::path::end(CurDir);
-    for (; CurDirIt != CurDirE && *CurDirIt == *FileIt; ++CurDirIt, ++FileIt)
-      llvm::sys::path::append(DirBuf, *CurDirIt);
-    if (std::distance(llvm::sys::path::begin(CurDir), CurDirIt) == 1) {
-      // The common prefix only the root; stripping it would cause
-      // LLVM diagnostic locations to be more confusing.
-      Dir = {};
-      File = RemappedFile;
-    } else {
-      for (; FileIt != FileE; ++FileIt)
-        llvm::sys::path::append(FileBuf, *FileIt);
-      Dir = DirBuf;
-      File = FileBuf;
-    }
-  } else {
-    Dir = CurDir;
-    File = RemappedFile;
-  }
-  llvm::DIFile *F =
-      DBuilder.createFile(File, Dir, CSInfo,
-                          getSource(SM, SM.getFileID(Loc)));
+  llvm::DIFile *F = DBuilder.createFile(
+      remapDIPath(PLoc.getFilename()), remapDIPath(getCurrentDirname()), CSInfo,
+      getSource(SM, SM.getFileID(Loc)));
 
-  DIFileCache[FileName.data()].reset(F);
+  DIFileCache[fname].reset(F);
   return F;
 }
 

clang/lib/CodeGen/CodeGenAction.cpp

@@ -549,16 +549,12 @@ const FullSourceLoc BackendConsumer::getBestLocationFromDebugLoc(
   SourceLocation DILoc;
 
   if (D.isLocationAvailable()) {
-    D.getLocation(Filename, Line, Column);
-    if (Line > 0) {
-      const FileEntry *FE = FileMgr.getFile(Filename);
-      if (!FE)
-        FE = FileMgr.getFile(D.getAbsolutePath());
-      if (FE) {
-        // If -gcolumn-info was not used, Column will be 0. This upsets the
-        // source manager, so pass 1 if Column is not set.
-        DILoc = SourceMgr.translateFileLineCol(FE, Line, Column ? Column : 1);
-      }
+    D.getLocation(&Filename, &Line, &Column);
+    const FileEntry *FE = FileMgr.getFile(Filename);
+    if (FE && Line > 0) {
+      // If -gcolumn-info was not used, Column will be 0. This upsets the
+      // source manager, so pass 1 if Column is not set.
+      DILoc = SourceMgr.translateFileLineCol(FE, Line, Column ? Column : 1);
     }
     BadDebugInfo = DILoc.isInvalid();
   }

clang/test/CodeGen/debug-info-abspath.c

@@ -1,15 +0,0 @@
-// RUN: %clang_cc1 -debug-info-kind=limited -triple %itanium_abi_triple \
-// RUN:   %s -emit-llvm -o - | FileCheck %s
-
-// RUN: cp %s %t.c
-// RUN: %clang_cc1 -debug-info-kind=limited -triple %itanium_abi_triple \
-// RUN:   %t.c -emit-llvm -o - | FileCheck %s --check-prefix=INTREE
-void foo() {}
-
-// Since %s is an absolute path, directory should be a nonempty
-// prefix, but the CodeGen part should be part of the filename.
-
-// CHECK: DIFile(filename: "{{.*}}CodeGen{{.*}}debug-info-abspath.c"
-// CHECK-SAME:   directory: "{{.+}}")
-
-// INTREE: DIFile({{.*}}directory: "{{.+}}CodeGen{{.*}}")

clang/test/CodeGen/debug-prefix-map.c

@@ -17,24 +17,18 @@ void test_rewrite_includes() {
 }
 
 // CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "/var/empty{{/|\\5C}}<stdin>"
-// CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "/var/empty{{[/\\]}}{{.*}}",
-// Dir should always be empty, but on Windows we can't recognize /var
-// as being an absolute path.
-// CHECK-NO-MAIN-FILE-NAME-SAME:    directory: "{{()|(.*:.*)}}")
-// CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "/var/empty{{[/\\]}}Inputs/stdio.h",
-// CHECK-NO-MAIN-FILE-NAME-SAME:    directory: "{{()|(.*:.*)}}")
+// CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "/var/empty{{[/\\]}}{{.*}}"
+// CHECK-NO-MAIN-FILE-NAME: !DIFile(filename: "/var/empty{{[/\\]}}Inputs/stdio.h"
 // CHECK-NO-MAIN-FILE-NAME-NOT: !DIFile(filename:
 
 // CHECK-EVIL: !DIFile(filename: "/var=empty{{[/\\]}}{{.*}}"
-// CHECK-EVIL: !DIFile(filename: "/var=empty{{[/\\]}}{{.*}}Inputs/stdio.h",
-// CHECK-EVIL-SAME:    directory: "{{()|(.*:.*)}}")
+// CHECK-EVIL: !DIFile(filename: "/var=empty{{[/\\]}}Inputs/stdio.h"
 // CHECK-EVIL-NOT: !DIFile(filename:
 
 // CHECK: !DIFile(filename: "/var/empty{{[/\\]}}{{.*}}"
-// CHECK: !DIFile(filename: "/var/empty{{[/\\]}}{{.*}}Inputs/stdio.h",
-// CHECK-SAME:    directory: "{{()|(.*:.*)}}")
+// CHECK: !DIFile(filename: "/var/empty{{[/\\]}}Inputs/stdio.h"
 // CHECK-NOT: !DIFile(filename:
 
-// CHECK-COMPILATION-DIR: !DIFile(filename: "{{.*}}", directory: "/var/empty")
-// CHECK-COMPILATION-DIR: !DIFile(filename: "{{.*}}Inputs/stdio.h", directory: "/var/empty")
+// CHECK-COMPILATION-DIR: !DIFile(filename: "/var/empty{{[/\\]}}{{.*}}", directory: "/var/empty")
+// CHECK-COMPILATION-DIR: !DIFile(filename: "/var/empty{{[/\\]}}Inputs/stdio.h", directory: "/var/empty")
 // CHECK-COMPILATION-DIR-NOT: !DIFile(filename:

clang/test/Modules/module-debuginfo-prefix.m

@@ -20,6 +20,4 @@
 @import DebugObjC;
 #endif
 
-// Dir should always be empty, but on Windows we can't recognize /var
-// as being an absolute path.
-// CHECK: !DIFile(filename: "/OVERRIDE/DebugObjC.h", directory: "{{()|(.*:.*)}}")
+// CHECK: !DIFile({{.*}}"/OVERRIDE/DebugObjC.h"