Subzero: Fix x86 floating-point constant emission

src/llvm2ice.cpp

 //===- subzero/src/llvm2ice.cpp - Driver for testing ----------------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file defines a driver that uses LLVM capabilities to parse a
 // bitcode file and build the LLVM IR, and then convert the LLVM basic
 // blocks, instructions, and operands into their Subzero equivalents.
 //
 //===----------------------------------------------------------------------===//
 
 #include "IceCfg.h"
 #include "IceCfgNode.h"
 #include "IceDefs.h"
 #include "IceGlobalContext.h"
 #include "IceInst.h"
 #include "IceOperand.h"
+#include "IceTargetLowering.h"
 #include "IceTypes.h"
 
 #include "llvm/IR/Constant.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/Instruction.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IRReader/IRReader.h"
@@ skipping 24 matching lines @@
 //
 class LLVM2ICEConverter {
 public:
   LLVM2ICEConverter(Ice::GlobalContext *Ctx)
       : Ctx(Ctx), Func(NULL), CurrentNode(NULL) {
     // All PNaCl pointer widths are 32 bits because of the sandbox
     // model.
     SubzeroPointerType = Ice::IceType_i32;
   }
 
+  // Caller is expected to delete the returned Ice::Cfg object.
   Ice::Cfg *convertFunction(const Function *F) {
     VarMap.clear();
     NodeMap.clear();
     Func = new Ice::Cfg(Ctx);
     Func->setFunctionName(F->getName());
     Func->setReturnType(convertType(F->getReturnType()));
     Func->setInternal(F->hasInternalLinkage());
 
     // The initial definition/use of each arg is the entry node.
     CurrentNode = mapBasicBlockToNode(&F->getEntryBlock());
@@ skipping 587 matching lines @@
   raw_os_ostream *Os =
       new raw_os_ostream(OutputFilename == "-" ? std::cout : Ofs);
   Os->SetUnbuffered();
   std::ofstream Lfs;
   if (LogFilename != "-") {
     Lfs.open(LogFilename.c_str(), std::ofstream::out);
   }
   raw_os_ostream *Ls = new raw_os_ostream(LogFilename == "-" ? std::cout : Lfs);
   Ls->SetUnbuffered();
 
+  Ice::Cfg *Func = NULL;
   Ice::GlobalContext Ctx(Ls, Os, VMask, TargetArch, OptLevel, TestPrefix);
 
   for (Module::const_iterator I = Mod->begin(), E = Mod->end(); I != E; ++I) {
     if (I->empty())
       continue;
     LLVM2ICEConverter FunctionConverter(&Ctx);
 
+    // Ideally, we would have deleted the Ice::Cfg object (Func) at
+    // the end of the previous iteration.  However, emitting the
+    // constant pool requires a valid Cfg object, so we need to defer
+    // deleting the last non-empty Cfg object until outside the loop
+    // and after emitting the constant pool.  TODO: Since all
+    // constants are globally pooled in the Ice::GlobalContext object,
+    // change all Ice::Constant related functions to use GlobalContext
+    // instead of Cfg, and then clean up this loop.
+    delete Func;

[JF, 2014/05/22 21:39:47]

A smart pointer be better here.

[Jim Stichnoth, 2014/05/22 23:48:28]

Done.

+    Func = NULL;
+
     Ice::Timer TConvert;
-    Ice::Cfg *Func = FunctionConverter.convertFunction(I);
+    Func = FunctionConverter.convertFunction(I);
     if (DisableInternal)
       Func->setInternal(false);
 
     if (SubzeroTimingEnabled) {
       std::cerr << "[Subzero timing] Convert function "
                 << Func->getFunctionName() << ": " << TConvert.getElapsedSec()
                 << " sec\n";
     }
 
     if (DisableTranslation) {
@@ skipping 14 matching lines @@
       Ice::Timer TEmit;
       Func->emit();
       if (SubzeroTimingEnabled) {
         std::cerr << "[Subzero timing] Emit function "
                   << Func->getFunctionName() << ": " << TEmit.getElapsedSec()
                   << " sec\n";
       }
     }
   }
 
+  if (!DisableTranslation && Func)
+    Func->getTarget()->emitConstants();
+
+  delete Func;
+  Func = NULL;

[JF, 2014/05/22 21:39:47]

Same.

[Jim Stichnoth, 2014/05/22 23:48:28]

Done.

+
   return ExitStatus;
 }