1 files changed, 33 insertions, 28 deletions

diff --git a/llvm/lib/Target/PIC16/PIC16InstrFormats.td b/llvm/lib/Target/PIC16/PIC16InstrFormats.td
index e8ecf6a3d32..e213ea847fc 100644
--- a/llvm/lib/Target/PIC16/PIC16InstrFormats.td
+++ b/llvm/lib/Target/PIC16/PIC16InstrFormats.td
@@ -1,4 +1,4 @@
-//===- PIC16RegisterInfo.td - PIC16 Register defs ------------*- tblgen -*-===//
+//===- PIC16InstrFormats.td - PIC16 Instruction Formats-------*- tblgen -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -21,16 +21,17 @@
 //===----------------------------------------------------------------------===//
 
 // Generic PIC16 Format
+// PIC16 Instructions are 14-bit wide.
+
+// FIXME: Add Cooper Specific Formats if any.
+
 class PIC16Inst<dag outs, dag ins, string asmstr, list<dag> pattern>
-        : Instruction 
-{
+  : Instruction {
   field bits<14> Inst;
 
   let Namespace = "PIC16";
-
   dag OutOperandList = outs;
   dag InOperandList = ins;
-
   let AsmString = asmstr;
   let Pattern = pattern;
 }
@@ -38,16 +39,18 @@ class PIC16Inst<dag outs, dag ins, string asmstr, list<dag> pattern>
 
 //===----------------------------------------------------------------------===//
 // Byte Oriented instruction class in PIC16 : <|opcode|d|f|>
+// opcode = 6 bits.
+// d = direction = 1 bit.
+// f = file register address = 7 bits.
 //===----------------------------------------------------------------------===//
 
-class ByteFormat<bits<6> op, dag outs, dag ins, string asmstr,
-                  list<dag> pattern>
-        :PIC16Inst<outs, ins, asmstr, pattern> 
-{
+class ByteFormat<bits<6> opcode, dag outs, dag ins, string asmstr,
+                 list<dag> pattern>
+  :PIC16Inst<outs, ins, asmstr, pattern> {
   bits<1>  d;
   bits<7>  f;
 
-  let Inst{13-8} = op;
+  let Inst{13-8} = opcode;
 
   let Inst{7} = d;
   let Inst{6-0} = f; 
@@ -55,15 +58,18 @@ class ByteFormat<bits<6> op, dag outs, dag ins, string asmstr,
 
 //===----------------------------------------------------------------------===//
 // Bit Oriented instruction class in PIC16 : <|opcode|b|f|>
+// opcode = 4 bits.
+// b = bit specifier = 3 bits.
+// f = file register address = 7 bits.
 //===----------------------------------------------------------------------===//
 
-class BitFormat<bits<4> op, dag outs, dag ins, string asmstr, list<dag> pattern>
-         : PIC16Inst<outs, ins, asmstr, pattern> 
-{
+class BitFormat<bits<4> opcode, dag outs, dag ins, string asmstr, 
+                list<dag> pattern>
+  : PIC16Inst<outs, ins, asmstr, pattern> {
   bits<3>  b;
   bits<7>  f;
 
-  let Inst{13-10} = op;
+  let Inst{13-10} = opcode;
 
   let Inst{9-7} = b;
   let Inst{6-0} = f; 
@@ -71,32 +77,32 @@ class BitFormat<bits<4> op, dag outs, dag ins, string asmstr, list<dag> pattern>
 
 //===----------------------------------------------------------------------===//
 // Literal Format instruction class in PIC16 : <|opcode|k|>
+// opcode = 6 bits
+// k = literal = 8 bits
 //===----------------------------------------------------------------------===//
 
-class LiteralFormat<bits<6> op, dag outs, dag ins, string asmstr, 
+class LiteralFormat<bits<6> opcode, dag outs, dag ins, string asmstr, 
                     list<dag> pattern>
-        : PIC16Inst<outs, ins, asmstr, pattern> 
-{
+  : PIC16Inst<outs, ins, asmstr, pattern> {
   bits<8> k;
-
   
-  let Inst{13-8} = op;
+  let Inst{13-8} = opcode;
 
   let Inst{7-0} = k; 
 }
 
 //===----------------------------------------------------------------------===//
 // Control Format instruction class in PIC16 : <|opcode|k|>
+// opcode = 3 bits.
+// k = jump address = 11 bits.
 //===----------------------------------------------------------------------===//
 
-class ControlFormat<bits<3> op, dag outs, dag ins, string asmstr, 
+class ControlFormat<bits<3> opcode, dag outs, dag ins, string asmstr, 
                     list<dag> pattern>
-        :PIC16Inst<outs, ins, asmstr, pattern> 
-{
+  : PIC16Inst<outs, ins, asmstr, pattern> {
   bits<11> k;
 
-  
-  let Inst{13-11} = op;
+  let Inst{13-11} = opcode;
 
   let Inst{10-0} = k; 
 }
@@ -105,8 +111,7 @@ class ControlFormat<bits<3> op, dag outs, dag ins, string asmstr,
 // Pseudo instruction class in PIC16
 //===----------------------------------------------------------------------===//
 
-class Pseudo<bits<8> op, dag outs, dag ins, string asmstr, list<dag> pattern>:
-      PIC16Inst<outs, ins, asmstr, pattern>
-{
-   let Inst{13-6} = op;
+class Pseudo<dag outs, dag ins, string asmstr, list<dag> pattern>
+  : PIC16Inst<outs, ins, asmstr, pattern> {
+   let Inst{13-6} = 0;
 }