Add Parser support for #pragma pack

 - Uses Action::ActOnPragmaPack
 - Test case is XFAIL pending verifier fixes.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@57066 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 108 insertions, 0 deletions

diff --git a/lib/Parse/ParsePragma.cpp b/lib/Parse/ParsePragma.cpp
new file mode 100644
index 0000000000..fbdb123bda
--- /dev/null
+++ b/lib/Parse/ParsePragma.cpp
@@ -0,0 +1,108 @@
+//===--- ParsePragma.cpp - Language specific pragma parsing ---------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the language specific #pragma handlers.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ParsePragma.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Parse/Action.h"
+using namespace clang;
+
+// #pragma pack(...) comes in the following delicious flavors:
+//   pack '(' [integer] ')'
+//   pack '(' 'show' ')'
+//   pack '(' ('push' | 'pop') [',' identifier] [, integer] ')'
+void PragmaPackHandler::HandlePragma(Preprocessor &PP, Token &PackTok) {
+  // FIXME: Should we be expanding macros here? My guess is no.
+  SourceLocation PackLoc = PackTok.getLocation();
+
+  Token Tok;
+  PP.Lex(Tok);
+  if (Tok.isNot(tok::l_paren)) {
+    PP.Diag(Tok.getLocation(), diag::warn_pragma_pack_expected_lparen);
+    return;
+  }
+
+  Action::PragmaPackKind Kind = Action::PPK_Default;
+  IdentifierInfo *Name = 0;
+  Action::ExprResult Alignment;
+  SourceLocation LParenLoc = Tok.getLocation();
+  PP.Lex(Tok);  
+  if (Tok.is(tok::numeric_constant)) {
+    Alignment = Actions.ActOnNumericConstant(Tok);
+    if (Alignment.isInvalid)
+      return;
+
+    PP.Lex(Tok);
+  } else if (Tok.is(tok::identifier)) {
+    const IdentifierInfo *II = Tok.getIdentifierInfo();
+    if (II == &PP.getIdentifierTable().get("show")) {
+      Kind = Action::PPK_Show;
+      PP.Lex(Tok);
+    } else {
+      if (II == &PP.getIdentifierTable().get("push")) {
+        Kind = Action::PPK_Push;
+      } else if (II == &PP.getIdentifierTable().get("pop")) {
+        Kind = Action::PPK_Pop;
+      } else {
+        PP.Diag(Tok.getLocation(), diag::warn_pragma_pack_invalid_action);
+        return;
+      }        
+      PP.Lex(Tok);
+    
+      if (Tok.is(tok::comma)) {
+        PP.Lex(Tok);
+        
+        if (Tok.is(tok::numeric_constant)) {
+          Alignment = Actions.ActOnNumericConstant(Tok);
+          if (Alignment.isInvalid)
+            return;
+
+          PP.Lex(Tok);
+        } else if (Tok.is(tok::identifier)) {
+          Name = Tok.getIdentifierInfo();
+          PP.Lex(Tok);
+          
+          if (Tok.is(tok::comma)) {
+            PP.Lex(Tok);
+            
+            if (Tok.isNot(tok::numeric_constant)) {
+              PP.Diag(Tok.getLocation(), diag::warn_pragma_pack_malformed, 
+                      II->getName());
+              return;
+            }
+            
+            Alignment = Actions.ActOnNumericConstant(Tok);
+            if (Alignment.isInvalid)
+              return;
+
+            PP.Lex(Tok);
+          }
+        } else {
+          PP.Diag(Tok.getLocation(), diag::warn_pragma_pack_malformed, 
+                  II->getName());
+          return;
+        }
+      }
+    }
+  } 
+
+  if (Tok.isNot(tok::r_paren)) {
+    PP.Diag(Tok.getLocation(), diag::warn_pragma_pack_expected_rparen);
+    return;
+  }
+
+  SourceLocation RParenLoc = Tok.getLocation();
+  Actions.ActOnPragmaPack(Kind, Name, Alignment.Val, PackLoc, 
+                          LParenLoc, RParenLoc);
+}
+