[llvm-commits] CVS: llvm/lib/Bitcode/Writer/BitcodeWriter.cpp ValueEnumerator.cpp

[Chris Lattner]

Changes in directory llvm/lib/Bitcode/Writer:

BitcodeWriter.cpp updated: 1.43 -> 1.44
ValueEnumerator.cpp updated: 1.11 -> 1.12
---
Log message:

implement the 'string constant' optimization.  This shrinks kc.bit from
2878544 to 2815788


---
Diffs of the changes:  (+11 -4)

 BitcodeWriter.cpp   |    6 ++++++
 ValueEnumerator.cpp |    9 +++++----
 2 files changed, 11 insertions(+), 4 deletions(-)


Index: llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
diff -u llvm/lib/Bitcode/Writer/BitcodeWriter.cpp:1.43 llvm/lib/Bitcode/Writer/BitcodeWriter.cpp:1.44
--- llvm/lib/Bitcode/Writer/BitcodeWriter.cpp:1.43	Sat May  5 19:21:25 2007
+++ llvm/lib/Bitcode/Writer/BitcodeWriter.cpp	Sat May  5 19:35:24 2007
@@ -484,6 +484,12 @@
         assert (CFP->getType() == Type::DoubleTy && "Unknown FP type!");
         Record.push_back(DoubleToBits((double)CFP->getValue()));
       }
+    } else if (isa<ConstantArray>(C) && cast<ConstantArray>(C)->isString()) {
+      // Emit constant strings specially.
+      Code = bitc::CST_CODE_STRING;
+      for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
+        Record.push_back(cast<ConstantInt>(C->getOperand(i))->getZExtValue());
+      
     } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(V) ||
                isa<ConstantVector>(V)) {
       Code = bitc::CST_CODE_AGGREGATE;


Index: llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
diff -u llvm/lib/Bitcode/Writer/ValueEnumerator.cpp:1.11 llvm/lib/Bitcode/Writer/ValueEnumerator.cpp:1.12
--- llvm/lib/Bitcode/Writer/ValueEnumerator.cpp:1.11	Fri May  4 00:21:47 2007
+++ llvm/lib/Bitcode/Writer/ValueEnumerator.cpp	Sat May  5 19:35:24 2007
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "ValueEnumerator.h"
+#include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Module.h"
 #include "llvm/TypeSymbolTable.h"
@@ -65,8 +66,6 @@
        I != E; ++I)
     EnumerateValue(I->getAliasee());
   
-  // FIXME: Implement the 'string constant' optimization.
-
   // Enumerate types used by the type symbol table.
   EnumerateTypeSymbolTable(M->getTypeSymbolTable());
 
@@ -105,8 +104,6 @@
   // Now that we rearranged the type table, rebuild TypeMap.
   for (unsigned i = 0, e = Types.size(); i != e; ++i)
     TypeMap[Types[i].first] = i+1;
-  
-  // FIXME: Sort value tables by frequency.
 }
 
 // Optimize constant ordering.
@@ -176,6 +173,10 @@
   if (const Constant *C = dyn_cast<Constant>(V)) {
     if (isa<GlobalValue>(C)) {
       // Initializers for globals are handled explicitly elsewhere.
+    } else if (isa<ConstantArray>(C) && cast<ConstantArray>(C)->isString()) {
+      // Do not enumerate the initializers for an array of simple characters.
+      // The initializers just polute the value table, and we emit the strings
+      // specially.
     } else {
       // This makes sure that if a constant has uses (for example an array of
       // const ints), that they are inserted also.