Simplify representation of forward value references in bitcode.

Simplify instruction records by adding concept of a forward type reference
map that maps ValueID's to types. Used to generate forward reference types
for instruction arguments that need a type because the forward reference
has not yet been generated.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3507
R=jvoung@chromium.org, mseaborn@chromium.org

Review URL: https://codereview.chromium.org/16963004

1 files changed, 22 insertions, 20 deletions

diff --git a/include/llvm/Bitcode/NaCl/NaClLLVMBitCodes.h b/include/llvm/Bitcode/NaCl/NaClLLVMBitCodes.h
index 3ad9242bd2..1c4d80efba 100644
--- a/include/llvm/Bitcode/NaCl/NaClLLVMBitCodes.h
+++ b/include/llvm/Bitcode/NaCl/NaClLLVMBitCodes.h
@@ -284,19 +284,20 @@ namespace naclbitc {
   enum NaClFunctionCodes {
     FUNC_CODE_DECLAREBLOCKS    =  1, // DECLAREBLOCKS: [n]
 
-    FUNC_CODE_INST_BINOP       =  2, // BINOP:      [opcode, ty, opval, opval]
-    FUNC_CODE_INST_CAST        =  3, // CAST:       [opcode, ty, opty, opval]
+    FUNC_CODE_INST_BINOP       =  2, // BINOP:      [opval, opval, opcode
+                                     //              [, flags]]
+    FUNC_CODE_INST_CAST        =  3, // CAST:       [opval, destty, castopc]
     FUNC_CODE_INST_GEP         =  4, // GEP:        [n x operands]
-    FUNC_CODE_INST_SELECT      =  5, // SELECT:     [ty, opval, opval, opval]
-    FUNC_CODE_INST_EXTRACTELT  =  6, // EXTRACTELT: [opty, opval, opval]
-    FUNC_CODE_INST_INSERTELT   =  7, // INSERTELT:  [ty, opval, opval, opval]
-    FUNC_CODE_INST_SHUFFLEVEC  =  8, // SHUFFLEVEC: [ty, opval, opval, opval]
-    FUNC_CODE_INST_CMP         =  9, // CMP:        [opty, opval, opval, pred]
+    FUNC_CODE_INST_SELECT      =  5, // SELECT:     [opval, opval, opval]
+    FUNC_CODE_INST_EXTRACTELT  =  6, // EXTRACTELT: [opval, opval]
+    FUNC_CODE_INST_INSERTELT   =  7, // INSERTELT:  [opval, opval, opval]
+    FUNC_CODE_INST_SHUFFLEVEC  =  8, // SHUFFLEVEC: [opval, opval, opval]
+    FUNC_CODE_INST_CMP         =  9, // CMP:        [opval, opval, pred]
 
-    FUNC_CODE_INST_RET         = 10, // RET:        [opty,opval<both optional>]
+    FUNC_CODE_INST_RET         = 10, // RET:        [opval<optional>]
     FUNC_CODE_INST_BR          = 11, // BR:         [bb#, bb#, cond] or [bb#]
     FUNC_CODE_INST_SWITCH      = 12, // SWITCH:     [opty, op0, op1, ...]
-    FUNC_CODE_INST_INVOKE      = 13, // INVOKE:     [attr, fnty, op0,op1, ...]
+    FUNC_CODE_INST_INVOKE      = 13, // No longer allowed.
     // 14 is unused.
     FUNC_CODE_INST_UNREACHABLE = 15, // UNREACHABLE
 
@@ -304,42 +305,43 @@ namespace naclbitc {
     // 17 is unused.
     // 18 is unused.
     FUNC_CODE_INST_ALLOCA      = 19, // ALLOCA:     [instty, op, align]
-    FUNC_CODE_INST_LOAD        = 20, // LOAD:       [opty, op, align, vol]
+    FUNC_CODE_INST_LOAD        = 20, // LOAD:       [op, align, vol]
     // 21 is unused.
     // 22 is unused.
     FUNC_CODE_INST_VAARG       = 23, // VAARG:      [valistty, valist, instty]
     // This store code encodes the pointer type, rather than the value type
     // this is so information only available in the pointer type (e.g. address
     // spaces) is retained.
-    FUNC_CODE_INST_STORE       = 24, // STORE:      [ptrty,ptr,val, align, vol]
+    FUNC_CODE_INST_STORE       = 24, // STORE:      [ptr, val, align, vol]
     // 25 is unused.
-    FUNC_CODE_INST_EXTRACTVAL  = 26, // EXTRACTVAL: [n x operands]
-    FUNC_CODE_INST_INSERTVAL   = 27, // INSERTVAL:  [n x operands]
+    FUNC_CODE_INST_EXTRACTVAL  = 26, // EXTRACTVAL: [opval, n x indices]
+    FUNC_CODE_INST_INSERTVAL   = 27, // INSERTVAL:  [opval, opval, n x indices]
     // fcmp/icmp returning Int1TY or vector of Int1Ty. Same as CMP, exists to
     // support legacy vicmp/vfcmp instructions.
-    FUNC_CODE_INST_CMP2        = 28, // CMP2:       [opty, opval, opval, pred]
+    FUNC_CODE_INST_CMP2        = 28, // CMP2:       [opval, opval, pred]
     // new select on i1 or [N x i1]
-    FUNC_CODE_INST_VSELECT     = 29, // VSELECT:    [ty,opval,opval,predty,pred]
+    FUNC_CODE_INST_VSELECT     = 29, // VSELECT:    [opval, opval, pred]
     FUNC_CODE_INST_INBOUNDS_GEP= 30, // INBOUNDS_GEP: [n x operands]
     FUNC_CODE_INST_INDIRECTBR  = 31, // INDIRECTBR: [opty, op0, op1, ...]
     // 32 is unused.
     FUNC_CODE_DEBUG_LOC_AGAIN  = 33, // DEBUG_LOC_AGAIN
 
-    FUNC_CODE_INST_CALL        = 34, // CALL:       [cc, fnty, fnid, args...]
+    FUNC_CODE_INST_CALL        = 34, // CALL:       [cc, fnid, args...]
 
     FUNC_CODE_DEBUG_LOC        = 35, // DEBUG_LOC:  [Line,Col,ScopeVal, IAVal]
     FUNC_CODE_INST_FENCE       = 36, // FENCE: [ordering, synchscope]
-    FUNC_CODE_INST_CMPXCHG     = 37, // CMPXCHG: [ptrty,ptr,cmp,new, align, vol,
+    FUNC_CODE_INST_CMPXCHG     = 37, // CMPXCHG: [ptr, cmp, new, align, vol,
                                      //           ordering, synchscope]
-    FUNC_CODE_INST_ATOMICRMW   = 38, // ATOMICRMW: [ptrty,ptr,val, operation,
+    FUNC_CODE_INST_ATOMICRMW   = 38, // ATOMICRMW: [ptr,val, operation,
                                      //             align, vol,
                                      //             ordering, synchscope]
     FUNC_CODE_INST_RESUME      = 39, // RESUME:     [opval]
     FUNC_CODE_INST_LANDINGPAD  = 40, // LANDINGPAD: [ty,val,val,num,id0,val0...]
-    FUNC_CODE_INST_LOADATOMIC  = 41, // LOAD: [opty, op, align, vol,
+    FUNC_CODE_INST_LOADATOMIC  = 41, // LOAD: [op, align, vol,
                                      //        ordering, synchscope]
-    FUNC_CODE_INST_STOREATOMIC = 42  // STORE: [ptrty,ptr,val, align, vol
+    FUNC_CODE_INST_STOREATOMIC = 42, // STORE: [ptr, val, align, vol
                                      //         ordering, synchscope]
+    FUNC_CODE_INST_FORWARDTYPEREF = 43 // TYPE: [opval, ty]
   };
 
   enum NaClUseListCodes {