[llvm] r192477 - Really fix CHECK-LABEL and CHECK-DAG interaction. This actually just restores the initial implementation that was in r186162 but got lost in some subsequent refactoring. More explicit variable names and comments are present now to hopefully prevent repeat regression, as well as another test.

[Stephen Lin]

Author: stephenwlin
Date: Fri Oct 11 13:38:36 2013
New Revision: 192477

URL: http://llvm.org/viewvc/llvm-project?rev=192477&view=rev
Log:
Really fix CHECK-LABEL and CHECK-DAG interaction. This actually just restores the initial implementation that was in r186162 but got lost in some subsequent refactoring. More explicit variable names and comments are present now to hopefully prevent repeat regression, as well as another test.

Added:
    llvm/trunk/test/FileCheck/check-label-dag-capture.txt
Modified:
    llvm/trunk/utils/FileCheck/FileCheck.cpp

Added: llvm/trunk/test/FileCheck/check-label-dag-capture.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/FileCheck/check-label-dag-capture.txt?rev=192477&view=auto
==============================================================================
--- llvm/trunk/test/FileCheck/check-label-dag-capture.txt (added)
+++ llvm/trunk/test/FileCheck/check-label-dag-capture.txt Fri Oct 11 13:38:36 2013
@@ -0,0 +1,11 @@
+; RUN: FileCheck -input-file %s %s
+
+bar
+foo
+foo
+zed
+
+CHECK-LABEL: {{^}}bar
+CHECK: {{^}}[[FOO:foo]]
+CHECK-DAG: {{^}}[[FOO]]
+CHECK-LABEL: {{^}}zed

Modified: llvm/trunk/utils/FileCheck/FileCheck.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/utils/FileCheck/FileCheck.cpp?rev=192477&r1=192476&r2=192477&view=diff
==============================================================================
--- llvm/trunk/utils/FileCheck/FileCheck.cpp (original)
+++ llvm/trunk/utils/FileCheck/FileCheck.cpp Fri Oct 11 13:38:36 2013
@@ -609,7 +609,7 @@ struct CheckString {
     : Pat(P), Loc(L), CheckTy(Ty) {}
 
   /// Check - Match check string and its "not strings" and/or "dag strings".
-  size_t Check(const SourceMgr &SM, StringRef Buffer,
+  size_t Check(const SourceMgr &SM, StringRef Buffer, bool IsLabelScanMode,
                size_t &MatchLen, StringMap<StringRef> &VariableTable) const;
 
   /// CheckNext - Verify there is a single line in the given buffer.
@@ -874,15 +874,21 @@ static unsigned CountNumNewlinesBetween(
 }
 
 size_t CheckString::Check(const SourceMgr &SM, StringRef Buffer,
-                          size_t &MatchLen,
+                          bool IsLabelScanMode, size_t &MatchLen,
                           StringMap<StringRef> &VariableTable) const {
   size_t LastPos = 0;
   std::vector<const Pattern *> NotStrings;
 
-  // Match "dag strings" (with mixed "not strings" if any).
-  LastPos = CheckDag(SM, Buffer, NotStrings, VariableTable);
-  if (LastPos == StringRef::npos)
-    return StringRef::npos;
+  // IsLabelScanMode is true when we are scanning forward to find CHECK-LABEL
+  // bounds; we have not processed variable definitions within the bounded block
+  // yet so cannot handle any final CHECK-DAG yet; this is handled when going
+  // over the block again (including the last CHECK-LABEL) in normal mode.
+  if (!IsLabelScanMode) {
+    // Match "dag strings" (with mixed "not strings" if any).
+    LastPos = CheckDag(SM, Buffer, NotStrings, VariableTable);
+    if (LastPos == StringRef::npos)
+      return StringRef::npos;
+  }
 
   // Match itself from the last position after matching CHECK-DAG.
   StringRef MatchBuffer = Buffer.substr(LastPos);
@@ -893,7 +899,9 @@ size_t CheckString::Check(const SourceMg
   }
   MatchPos += LastPos;
 
-  if (CheckTy != Check::CheckLabel) {
+  // Similar to the above, in "label-scan mode" we can't yet handle CHECK-NEXT
+  // or CHECK-NOT
+  if (!IsLabelScanMode) {
     StringRef SkippedRegion = Buffer.substr(LastPos, MatchPos);
 
     // If this check is a "CHECK-NEXT", verify that the previous match was on
@@ -1117,7 +1125,7 @@ int main(int argc, char **argv) {
 
       // Scan to next CHECK-LABEL match, ignoring CHECK-NOT and CHECK-DAG
       size_t MatchLabelLen = 0;
-      size_t MatchLabelPos = CheckLabelStr.Check(SM, Buffer,
+      size_t MatchLabelPos = CheckLabelStr.Check(SM, Buffer, true,
                                                  MatchLabelLen, VariableTable);
       if (MatchLabelPos == StringRef::npos) {
         hasError = true;
@@ -1135,7 +1143,7 @@ int main(int argc, char **argv) {
       // Check each string within the scanned region, including a second check
       // of any final CHECK-LABEL (to verify CHECK-NOT and CHECK-DAG)
       size_t MatchLen = 0;
-      size_t MatchPos = CheckStr.Check(SM, CheckRegion, MatchLen,
+      size_t MatchPos = CheckStr.Check(SM, CheckRegion, false, MatchLen,
                                        VariableTable);
 
       if (MatchPos == StringRef::npos) {