64-bit prep

Preparation for 64-bit roll.
  o Eliminated storing pointers in 32-bit int slots in LIR.
  o General size reductions of common structures to reduce impact
    of doubled pointer sizes:
    - BasicBlock struct was 72 bytes, now is 48.
    - MIR struct was 72 bytes, now is 64.
    - RegLocation was 12 bytes, now is 8.
  o Generally replaced uses of BasicBlock* pointers with 16-bit Ids.
  o Replaced several doubly-linked lists with singly-linked to save
    one stored pointer per node.
  o We had quite a few uses of uintptr_t's that were a holdover from
    the JIT (which used pointers to mapped dex & actual code cache
    addresses rather than trace-relative offsets).  Replaced those with
    uint32_t's.
  o Clean up handling of embedded data for switch tables and array data.
  o Miscellaneous cleanup.

I anticipate one or two additional CLs to reduce the size of MIR and LIR
structs.

Change-Id: I58e426d3f8e5efe64c1146b2823453da99451230
diff --git a/compiler/dex/quick/x86/fp_x86.cc b/compiler/dex/quick/x86/fp_x86.cc
index f736b5e..c9d6bfc 100644
--- a/compiler/dex/quick/x86/fp_x86.cc
+++ b/compiler/dex/quick/x86/fp_x86.cc
@@ -284,8 +284,8 @@
 
 void X86Mir2Lir::GenFusedFPCmpBranch(BasicBlock* bb, MIR* mir, bool gt_bias,
                                      bool is_double) {
-  LIR* taken = &block_label_list_[bb->taken->id];
-  LIR* not_taken = &block_label_list_[bb->fall_through->id];
+  LIR* taken = &block_label_list_[bb->taken];
+  LIR* not_taken = &block_label_list_[bb->fall_through];
   LIR* branch = NULL;
   RegLocation rl_src1;
   RegLocation rl_src2;