From e00b59f954c7e27d9d34abf90bfac969fb12f19a Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Sun, 4 Apr 2010 17:57:56 +0000
Subject: [PATCH] lazily allocate the GCMetadataPrinters map and remove
 DenseMap from the AsmPrinter interface.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100331 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/AsmPrinter.h     | 11 ++++-----
 lib/CodeGen/AsmPrinter/AsmPrinter.cpp | 35 +++++++++++++++++++--------
 2 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/include/llvm/CodeGen/AsmPrinter.h b/include/llvm/CodeGen/AsmPrinter.h
index 080dc16e211..a46fa4955cd 100644
--- a/include/llvm/CodeGen/AsmPrinter.h
+++ b/include/llvm/CodeGen/AsmPrinter.h
@@ -19,7 +19,6 @@
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/Support/DebugLoc.h"
 #include "llvm/Target/TargetMachine.h"
-#include "llvm/ADT/DenseMap.h"
 
 namespace llvm {
   class BlockAddress;
@@ -60,11 +59,6 @@ namespace llvm {
   class AsmPrinter : public MachineFunctionPass {
     static char ID;
 
-    // GCMetadataPrinters - The garbage collection metadata printer table.
-    typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
-    typedef gcp_map_type::iterator gcp_iterator;
-    gcp_map_type GCMetadataPrinters;
-
     /// If VerboseAsm is set, a pointer to the loop info for this
     /// function.
     ///
@@ -125,6 +119,11 @@ namespace llvm {
     ///
     bool VerboseAsm;
 
+    
+  private:
+    // GCMetadataPrinters - The garbage collection metadata printer table.
+    void *GCMetadataPrinters;  // Really a DenseMap.
+    
     /// Private state for PrintSpecial()
     // Assign a unique ID to this machine instruction.
     mutable const MachineInstr *LastMI;
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 34dc9cd1f4e..9007d0d0beb 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -55,20 +55,34 @@ STATISTIC(EmittedInsts, "Number of machine instrs printed");
 
 char AsmPrinter::ID = 0;
 
+typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
+static gcp_map_type &getGCMap(void *&P) {
+  if (P == 0)
+    P = new gcp_map_type();
+  return *(gcp_map_type*)P;
+}
+
+
 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
-  : MachineFunctionPass(&ID), 
+  : MachineFunctionPass(&ID),
     TM(tm), MAI(tm.getMCAsmInfo()), TRI(tm.getRegisterInfo()),
     OutContext(Streamer.getContext()),
     OutStreamer(Streamer),
     LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
   DW = 0; MMI = 0;
+  GCMetadataPrinters = 0;
   VerboseAsm = Streamer.isVerboseAsm();
 }
 
 AsmPrinter::~AsmPrinter() {
-  for (gcp_iterator I = GCMetadataPrinters.begin(),
-                    E = GCMetadataPrinters.end(); I != E; ++I)
-    delete I->second;
+  if (GCMetadataPrinters != 0) {
+    gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
+    
+    for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
+      delete I->second;
+    delete &GCMap;
+    GCMetadataPrinters = 0;
+  }
   
   delete &OutStreamer;
 }
@@ -1829,8 +1843,8 @@ void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
 /// exactly one predecessor and the control transfer mechanism between
 /// the predecessor and this block is a fall-through.
-bool AsmPrinter::isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) 
-    const {
+bool AsmPrinter::
+isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
   // If this is a landing pad, it isn't a fall through.  If it has no preds,
   // then nothing falls through to it.
   if (MBB->isLandingPad() || MBB->pred_empty())
@@ -1862,9 +1876,10 @@ bool AsmPrinter::isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB)
 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
   if (!S->usesMetadata())
     return 0;
-  
-  gcp_iterator GCPI = GCMetadataPrinters.find(S);
-  if (GCPI != GCMetadataPrinters.end())
+
+  gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
+  gcp_map_type::iterator GCPI = GCMap.find(S);
+  if (GCPI != GCMap.end())
     return GCPI->second;
   
   const char *Name = S->getName().c_str();
@@ -1875,7 +1890,7 @@ GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
     if (strcmp(Name, I->getName()) == 0) {
       GCMetadataPrinter *GMP = I->instantiate();
       GMP->S = S;
-      GCMetadataPrinters.insert(std::make_pair(S, GMP));
+      GCMap.insert(std::make_pair(S, GMP));
       return GMP;
     }
   
-- 
2.34.1