Fix a bug where the DWARF emitter in the JIT was not initializing alignment

bytes.  libgcc doesn't seem to mind, but if you pass this DWARF to GDB, it
doesn't like it.  

Also make the JIT memory manager to initialize it's memory to garbage in debug
mode, so that it's easier to find bugs like these in the future.

llvm-svn: 79674

1 files changed, 18 insertions, 28 deletions

diff --git a/llvm/lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp b/llvm/lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp
index c661168487a..a3a050635fe 100644
--- a/llvm/lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp
+++ b/llvm/lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp
@@ -396,20 +396,10 @@ unsigned char* JITDwarfEmitter::EmitExceptionTable(MachineFunction* MF,
                         TargetAsmInfo::getULEB128Size(SizeSites) + 
                         SizeSites + SizeActions + SizeTypes;
 
-  unsigned TotalSize = sizeof(int8_t) + // LPStart format
-                       sizeof(int8_t) + // TType format
-                       TargetAsmInfo::getULEB128Size(TypeOffset) + // TType base offset
-                       TypeOffset;
-
-  unsigned SizeAlign = (4 - TotalSize) & 3;
-
   // Begin the exception table.
-  JCE->emitAlignment(4);
-  for (unsigned i = 0; i != SizeAlign; ++i) {
-    JCE->emitByte(0);
-    // Asm->EOL("Padding");
-  }
-  
+  JCE->emitAlignmentWithFill(4, 0);
+  // Asm->EOL("Padding");
+
   unsigned char* DwarfExceptionTable = (unsigned char*)JCE->getCurrentPCValue();
 
   // Emit the header.
@@ -496,8 +486,8 @@ unsigned char* JITDwarfEmitter::EmitExceptionTable(MachineFunction* MF,
     JCE->emitULEB128Bytes(TypeID);
     //Asm->EOL("Filter TypeInfo index");
   }
-  
-  JCE->emitAlignment(4);
+
+  JCE->emitAlignmentWithFill(4, 0);
 
   return DwarfExceptionTable;
 }
@@ -546,11 +536,12 @@ JITDwarfEmitter::EmitCommonEHFrame(const Function* Personality) const {
   std::vector<MachineMove> Moves;
   RI->getInitialFrameState(Moves);
   EmitFrameMoves(0, Moves);
-  JCE->emitAlignment(PointerSize);
-  
-  JCE->emitInt32At((uintptr_t*)StartCommonPtr, 
-              (uintptr_t)((unsigned char*)JCE->getCurrentPCValue() - 
-                          FrameCommonBeginPtr));
+
+  JCE->emitAlignmentWithFill(PointerSize, dwarf::DW_CFA_nop);
+
+  JCE->emitInt32At((uintptr_t*)StartCommonPtr,
+                   (uintptr_t)((unsigned char*)JCE->getCurrentPCValue() -
+                               FrameCommonBeginPtr));
 
   return StartCommonPtr;
 }
@@ -590,14 +581,14 @@ JITDwarfEmitter::EmitEHFrame(const Function* Personality,
   // Indicate locations of function specific  callee saved registers in
   // frame.
   EmitFrameMoves((intptr_t)StartFunction, MMI->getFrameMoves());
-      
-  JCE->emitAlignment(PointerSize);
-  
+
+  JCE->emitAlignmentWithFill(PointerSize, dwarf::DW_CFA_nop);
+
   // Indicate the size of the table
-  JCE->emitInt32At((uintptr_t*)StartEHPtr, 
-              (uintptr_t)((unsigned char*)JCE->getCurrentPCValue() - 
-                          StartEHPtr));
-  
+  JCE->emitInt32At((uintptr_t*)StartEHPtr,
+                   (uintptr_t)((unsigned char*)JCE->getCurrentPCValue() -
+                               StartEHPtr));
+
   // Double zeroes for the unwind runtime
   if (PointerSize == 8) {
     JCE->emitInt64(0);
@@ -606,7 +597,6 @@ JITDwarfEmitter::EmitEHFrame(const Function* Personality,
     JCE->emitInt32(0);
     JCE->emitInt32(0);
   }
-
   
   return StartEHPtr;
 }