Simplify globals in PNaCl wire format based on normalized constants.

Generates simple global variable records, followed by list of records defining
byte initialization and relocations.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3504
R=mseaborn@chromium.org

Review URL: https://codereview.chromium.org/18111002

1 files changed, 12 insertions, 10 deletions

diff --git a/lib/Bitcode/NaCl/Writer/NaClValueEnumerator.cpp b/lib/Bitcode/NaCl/Writer/NaClValueEnumerator.cpp
index feb14cdb0c..393c5bc934 100644
--- a/lib/Bitcode/NaCl/Writer/NaClValueEnumerator.cpp
+++ b/lib/Bitcode/NaCl/Writer/NaClValueEnumerator.cpp
@@ -42,16 +42,21 @@ NaClValueEnumerator::NaClValueEnumerator(const Module *M) {
   // constructor completes.
   TypeCountMapType count_map;
   TypeCountMap = &count_map;
-  // Enumerate the global variables.
-  for (Module::const_global_iterator I = M->global_begin(),
-         E = M->global_end(); I != E; ++I)
-    EnumerateValue(I);
 
-  // Enumerate the functions.
+  // Enumerate the functions. Note: We do this before global
+  // variables, so that global variable initializations can refer to
+  // the functions without a forward reference.
   for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
     EnumerateValue(I);
   }
 
+  // Enumerate the global variables.
+  FirstGlobalVarID = Values.size();
+  for (Module::const_global_iterator I = M->global_begin(),
+         E = M->global_end(); I != E; ++I)
+    EnumerateValue(I);
+  NumGlobalVarIDs = Values.size() - FirstGlobalVarID;
+
   // Enumerate the aliases.
   for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
        I != E; ++I)
@@ -60,11 +65,8 @@ NaClValueEnumerator::NaClValueEnumerator(const Module *M) {
   // Remember what is the cutoff between globalvalue's and other constants.
   unsigned FirstConstant = Values.size();
 
-  // Enumerate the global variable initializers.
-  for (Module::const_global_iterator I = M->global_begin(),
-         E = M->global_end(); I != E; ++I)
-    if (I->hasInitializer())
-      EnumerateValue(I->getInitializer());
+  // Skip global variable initializers since they are handled within
+  // WriteGlobalVars of file NaClBitcodeWriter.cpp.
 
   // Enumerate the aliasees.
   for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();