Compiler constant handling rework

In preparation for de-optimization, reworked the constant
handling mechanism.  Also took advantage of knowledge of
constant operands (particularly for long operations).

Significant performance improvements for Mandelbrot
(~60 seconds to ~34 seconds).  Minor improvements in other
benchmarks.

The new constant handling breaks two of the existing
optimization passes: "Skip Large Method" and "Load/Store
Elimization."

I don't intend to update the large method optimization
because it will be superceeded by the upcoming interpreter/
fingerprinting mechanism.  Leaving the code in place for
now in order to compare compile-time improvements with
fingerprinting/interpret.  All related code will be deleted
when that is complete.

The load/store elimination pass needs some rework to handle
uses of multiple-register loads and stores.  It will be
updated & restored in a future CL.

Change-Id: Ia979abaf51b8ae81bbb0428031cbcea854625fac
diff --git a/src/compiler/codegen/x86/utility_x86.cc b/src/compiler/codegen/x86/utility_x86.cc
index 4f9e28b..4cc2c18 100644
--- a/src/compiler/codegen/x86/utility_x86.cc
+++ b/src/compiler/codegen/x86/utility_x86.cc
@@ -50,11 +50,26 @@
   return res;
 }
 
-bool X86Codegen::InexpensiveConstant(int reg, int value)
+bool X86Codegen::InexpensiveConstantInt(int32_t value)
 {
   return true;
 }
 
+bool X86Codegen::InexpensiveConstantFloat(int32_t value)
+{
+  return false;
+}
+
+bool X86Codegen::InexpensiveConstantLong(int64_t value)
+{
+  return true;
+}
+
+bool X86Codegen::InexpensiveConstantDouble(int64_t value)
+{
+  return false; // TUNING
+}
+
 /*
  * Load a immediate using a shortcut if possible; otherwise
  * grab from the per-translation literal pool.  If target is
@@ -316,13 +331,14 @@
   return NewLIR2(cu, opcode, rBase, disp);
 }
 
-LIR* X86Codegen::LoadConstantValueWide(CompilationUnit *cu, int r_dest_lo,
-                                       int r_dest_hi, int val_lo, int val_hi)
+LIR* X86Codegen::LoadConstantWide(CompilationUnit *cu, int r_dest_lo, int r_dest_hi, int64_t value)
 {
+    int32_t val_lo = Low32Bits(value);
+    int32_t val_hi = High32Bits(value);
     LIR *res;
     if (X86_FPREG(r_dest_lo)) {
       DCHECK(X86_FPREG(r_dest_hi));  // ignore r_dest_hi
-      if (val_lo == 0 && val_hi == 0) {
+      if (value == 0) {
         return NewLIR2(cu, kX86XorpsRR, r_dest_lo, r_dest_lo);
       } else {
         if (val_lo == 0) {