[FileCheck] Introduce substitution subclasses

Summary:
With now a clear distinction between string and numeric substitutions,
this patch introduces separate classes to represent them with a parent
class implementing the common interface. Diagnostics in
printSubstitutions() are also adapted to not require knowing which
substitution is being looked at since it does not hinder clarity and
makes the implementation simpler.

Reviewers: jhenderson, jdenny, probinson, arichardson

Subscribers: llvm-commits, probinson, arichardson, hiraditya

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62241

llvm-svn: 361446

1 files changed, 39 insertions, 27 deletions

diff --git a/llvm/lib/Support/FileCheck.cpp b/llvm/lib/Support/FileCheck.cpp
index 5eb0c64..a2b0f84 100644
--- a/llvm/lib/Support/FileCheck.cpp
+++ b/llvm/lib/Support/FileCheck.cpp
@@ -52,14 +52,14 @@ StringRef FileCheckNumExpr::getUndefVarName() const {
   return StringRef();
 }
 
-llvm::Optional<std::string> FileCheckSubstitution::getResult() const {
-  if (IsNumSubst) {
-    llvm::Optional<uint64_t> EvaluatedValue = NumExpr->eval();
-    if (!EvaluatedValue)
-      return llvm::None;
-    return utostr(*EvaluatedValue);
-  }
+llvm::Optional<std::string> FileCheckNumericSubstitution::getResult() const {
+  llvm::Optional<uint64_t> EvaluatedValue = NumExpr->eval();
+  if (!EvaluatedValue)
+    return llvm::None;
+  return utostr(*EvaluatedValue);
+}
 
+llvm::Optional<std::string> FileCheckStringSubstitution::getResult() const {
   // Look up the value and escape it so that we can put it into the regex.
   llvm::Optional<StringRef> VarVal = Context->getPatternVarValue(FromStr);
   if (!VarVal)
@@ -67,12 +67,13 @@ llvm::Optional<std::string> FileCheckSubstitution::getResult() const {
   return Regex::escape(*VarVal);
 }
 
-StringRef FileCheckSubstitution::getUndefVarName() const {
-  if (IsNumSubst)
-    // Although a use of an undefined numeric variable is detected at parse
-    // time, a numeric variable can be undefined later by ClearLocalVariables.
-    return NumExpr->getUndefVarName();
+StringRef FileCheckNumericSubstitution::getUndefVarName() const {
+  // Although a use of an undefined numeric variable is detected at parse
+  // time, a numeric variable can be undefined later by ClearLocalVariables.
+  return NumExpr->getUndefVarName();
+}
 
+StringRef FileCheckStringSubstitution::getUndefVarName() const {
   if (!Context->getPatternVarValue(FromStr))
     return FromStr;
 
@@ -385,11 +386,11 @@ bool FileCheckPattern::ParsePattern(StringRef PatternStr, StringRef Prefix,
         } else {
           // Handle substitution of string variables ([[<var>]]) defined in
           // previous CHECK patterns, and substitution of numeric expressions.
-          FileCheckSubstitution Substitution =
-              IsNumBlock ? FileCheckSubstitution(Context, MatchStr, NumExpr,
-                                                 SubstInsertIdx)
-                         : FileCheckSubstitution(Context, MatchStr,
-                                                 SubstInsertIdx);
+          FileCheckSubstitution *Substitution =
+              IsNumBlock
+                  ? Context->makeNumericSubstitution(MatchStr, NumExpr,
+                                                     SubstInsertIdx)
+                  : Context->makeStringSubstitution(MatchStr, SubstInsertIdx);
           Substitutions.push_back(Substitution);
         }
         continue;
@@ -471,12 +472,12 @@ size_t FileCheckPattern::match(StringRef Buffer, size_t &MatchLen) const {
     // handled by back-references.
     for (const auto &Substitution : Substitutions) {
       // Substitute and check for failure (e.g. use of undefined variable).
-      llvm::Optional<std::string> Value = Substitution.getResult();
+      llvm::Optional<std::string> Value = Substitution->getResult();
       if (!Value)
         return StringRef::npos;
 
       // Plop it into the regex at the adjusted offset.
-      TmpStr.insert(TmpStr.begin() + Substitution.getIndex() + InsertOffset,
+      TmpStr.insert(TmpStr.begin() + Substitution->getIndex() + InsertOffset,
                     Value->begin(), Value->end());
       InsertOffset += Value->size();
     }
@@ -532,24 +533,20 @@ void FileCheckPattern::printSubstitutions(const SourceMgr &SM, StringRef Buffer,
     for (const auto &Substitution : Substitutions) {
       SmallString<256> Msg;
       raw_svector_ostream OS(Msg);
-      bool IsNumSubst = Substitution.isNumSubst();
-      llvm::Optional<std::string> MatchedValue = Substitution.getResult();
+      llvm::Optional<std::string> MatchedValue = Substitution->getResult();
 
       // Substitution failed or is not known at match time, print the undefined
       // variable it uses.
       if (!MatchedValue) {
-        StringRef UndefVarName = Substitution.getUndefVarName();
+        StringRef UndefVarName = Substitution->getUndefVarName();
         if (UndefVarName.empty())
           continue;
         OS << "uses undefined variable \"";
         OS.write_escaped(UndefVarName) << "\"";
       } else {
         // Substitution succeeded. Print substituted value.
-        if (IsNumSubst)
-          OS << "with numeric expression \"";
-        else
-          OS << "with string variable \"";
-        OS.write_escaped(Substitution.getFromString()) << "\" equal to \"";
+        OS << "with \"";
+        OS.write_escaped(Substitution->getFromString()) << "\" equal to \"";
         OS.write_escaped(*MatchedValue) << "\"";
       }
 
@@ -653,6 +650,21 @@ FileCheckPatternContext::makeNumericVariable(StringRef Name, uint64_t Value) {
   return NumericVariables.back().get();
 }
 
+FileCheckSubstitution *
+FileCheckPatternContext::makeStringSubstitution(StringRef VarName,
+                                                size_t InsertIdx) {
+  Substitutions.push_back(
+      llvm::make_unique<FileCheckStringSubstitution>(this, VarName, InsertIdx));
+  return Substitutions.back().get();
+}
+
+FileCheckSubstitution *FileCheckPatternContext::makeNumericSubstitution(
+    StringRef Expr, FileCheckNumExpr *NumExpr, size_t InsertIdx) {
+  Substitutions.push_back(llvm::make_unique<FileCheckNumericSubstitution>(
+      this, Expr, NumExpr, InsertIdx));
+  return Substitutions.back().get();
+}
+
 size_t FileCheckPattern::FindRegexVarEnd(StringRef Str, SourceMgr &SM) {
   // Offset keeps track of the current offset within the input Str
   size_t Offset = 0;