commit 2ed2e62498b7cccf951b7c671498625cecd2a862
author Evgeny Mankov <evgeny.mankov@gmail.com> Tue Aug 27 22:15:32 2019 +0000
committer Evgeny Mankov <evgeny.mankov@gmail.com> Tue Aug 27 22:15:32 2019 +0000
tree 55eec008498bc42eae38b77d850d0c7e8a042a48
parent 1fac68b0dc19b03fd2c5e9856f0f2c5a11691348

[preprocessor] Add an opportunity to retain excluded conditional blocks

It is handy for clang tooling, for instance, in source to source transformation.

Reviewers: vpykhtin (Valery Pykhtin), erichkeane (Erich Keane)

Subscribers: rsmith (Richard Smith), akyrtzi (Argyrios Kyrtzidis)

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66597

llvm-svn: 370123

clang/lib/Lex/PPDirectives.cpp

diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp
index 5eac1da..525f95b 100644
--- a/clang/lib/Lex/PPDirectives.cpp
+++ b/clang/lib/Lex/PPDirectives.cpp
@@ -2855,6 +2855,9 @@
       Callbacks->Ifdef(DirectiveTok.getLocation(), MacroNameTok, MD);
   }
 
+  bool RetainExcludedCB = PPOpts->RetainExcludedConditionalBlocks &&
+    getSourceManager().isInMainFile(DirectiveTok.getLocation());
+
   // Should we include the stuff contained by this directive?
   if (PPOpts->SingleFileParseMode && !MI) {
     // In 'single-file-parse mode' undefined identifiers trigger parsing of all
@@ -2862,7 +2865,7 @@
     CurPPLexer->pushConditionalLevel(DirectiveTok.getLocation(),
                                      /*wasskip*/false, /*foundnonskip*/false,
                                      /*foundelse*/false);
-  } else if (!MI == isIfndef) {
+  } else if (!MI == isIfndef || RetainExcludedCB) {
     // Yes, remember that we are inside a conditional, then lex the next token.
     CurPPLexer->pushConditionalLevel(DirectiveTok.getLocation(),
                                      /*wasskip*/false, /*foundnonskip*/true,
@@ -2903,13 +2906,16 @@
         IfToken.getLocation(), DER.ExprRange,
         (ConditionalTrue ? PPCallbacks::CVK_True : PPCallbacks::CVK_False));
 
+  bool RetainExcludedCB = PPOpts->RetainExcludedConditionalBlocks &&
+    getSourceManager().isInMainFile(IfToken.getLocation());
+
   // Should we include the stuff contained by this directive?
   if (PPOpts->SingleFileParseMode && DER.IncludedUndefinedIds) {
     // In 'single-file-parse mode' undefined identifiers trigger parsing of all
     // the directive blocks.
     CurPPLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false,
                                      /*foundnonskip*/false, /*foundelse*/false);
-  } else if (ConditionalTrue) {
+  } else if (ConditionalTrue || RetainExcludedCB) {
     // Yes, remember that we are inside a conditional, then lex the next token.
     CurPPLexer->pushConditionalLevel(IfToken.getLocation(), /*wasskip*/false,
                                    /*foundnonskip*/true, /*foundelse*/false);
@@ -2971,7 +2977,10 @@
   if (Callbacks)
     Callbacks->Else(Result.getLocation(), CI.IfLoc);
 
-  if (PPOpts->SingleFileParseMode && !CI.FoundNonSkip) {
+  bool RetainExcludedCB = PPOpts->RetainExcludedConditionalBlocks &&
+    getSourceManager().isInMainFile(Result.getLocation());
+
+  if ((PPOpts->SingleFileParseMode && !CI.FoundNonSkip) || RetainExcludedCB) {
     // In 'single-file-parse mode' undefined identifiers trigger parsing of all
     // the directive blocks.
     CurPPLexer->pushConditionalLevel(CI.IfLoc, /*wasskip*/false,
@@ -3013,7 +3022,10 @@
     Callbacks->Elif(ElifToken.getLocation(), ConditionRange,
                     PPCallbacks::CVK_NotEvaluated, CI.IfLoc);
 
-  if (PPOpts->SingleFileParseMode && !CI.FoundNonSkip) {
+  bool RetainExcludedCB = PPOpts->RetainExcludedConditionalBlocks &&
+    getSourceManager().isInMainFile(ElifToken.getLocation());
+
+  if ((PPOpts->SingleFileParseMode && !CI.FoundNonSkip) || RetainExcludedCB) {
     // In 'single-file-parse mode' undefined identifiers trigger parsing of all
     // the directive blocks.
     CurPPLexer->pushConditionalLevel(ElifToken.getLocation(), /*wasskip*/false,