/******************************************************************************/
/* */
/* Copyright (c) 1999 Sun Microsystems, Inc. All rights reserved. */
/* */
/* The contents of this file are subject to the current version of the Sun */
/* Community Source License, microSPARCII ("the License"). You may not use */
/* this file except in compliance with the License. You may obtain a copy */
/* of the License by searching for "Sun Community Source License" on the */
/* World Wide Web at http://www.sun.com. See the License for the rights, */
/* obligations, and limitations governing use of the contents of this file. */
/* */
/* Sun Microsystems, Inc. has intellectual property rights relating to the */
/* technology embodied in these files. In particular, and without limitation, */
/* these intellectual property rights may include one or more U.S. patents, */
/* foreign patents, or pending applications. */
/* */
/* Sun, Sun Microsystems, the Sun logo, all Sun-based trademarks and logos, */
/* Solaris, Java and all Java-based trademarks and logos are trademarks or */
/* registered trademarks of Sun Microsystems, Inc. in the United States and */
/* other countries. microSPARC is a trademark or registered trademark of */
/* SPARC International, Inc. All SPARC trademarks are used under license and */
/* are trademarks or registered trademarks of SPARC International, Inc. in */
/* the United States and other countries. Products bearing SPARC trademarks */
/* are based upon an architecture developed by Sun Microsystems, Inc. */
/* */
/******************************************************************************/
/***************************************************************************
****************************************************************************
***
*** Program File: @(#)icceval.v
***
****************************************************************************
****************************************************************************/
//------------------------------------------------------------------------------
![[Up: Mdecode icceval]](v2html-up.gif)
module Micceval
(bicc_taken,
d_cond, ccm, alu_cc_next, load_cc,
eopc_hidiv3, det_divovf, ccN_noninv, ccZ_noninv
);
/*
* For SUNERGY Puma: d_cond used to be condm, but was changed since
* we need to decide if a branch is taken in the D cycle of the branch.
* condm is in the E-cycle.
*/
output bicc_taken
; // Integer CC's + COND evaluate TRUE in D
input [3:0] d_cond
; // master latched COND field of BICC in D
input [3:0] ccm
; // master latched condition codes
input [3:0] alu_cc_next
; // CC's direct from ALU
input load_cc
; // control to select ALU's CC.
input eopc_hidiv3
; // hidiv 3 in E
input det_divovf
; // ovf detected in IDIV
input ccN_noninv
; // non-inverted ccN (alu_cc_next[3]) from Mexec
input ccZ_noninv
; // non-inverted ccZ (alu_cc_next[2]) from Mexec
wire [1:0] alu_cc_lo
;
assign alu_cc_lo[1] =
alu_cc_next[1] & ~eopc_hidiv3
| eopc_hidiv3 & det_divovf;
assign alu_cc_lo[0] =
alu_cc_next[0] & ~eopc_hidiv3;
// note that the control logic receives alu_cc_next[3:2] inverted.
// we must reinvert here. ======> this is old note
// 9-15-96 : to speed up path, bring in non-inverted signals from Mexec.
// wire alu_cc_next_act3 = ~alu_cc_next[3];
// wire alu_cc_next_act2 = ~alu_cc_next[2];
wire Nm
=
// synopsys translate_off
(load_cc===1'bx) ? 'bx :
// synopsys translate_on
load_cc ? ccN_noninv : ccm[3];
wire Zm
=
// synopsys translate_off
(load_cc===1'bx) ? 'bx :
// synopsys translate_on
load_cc ? ccZ_noninv : ccm[2];
wire Vm
=
// synopsys translate_off
(load_cc===1'bx) ? 'bx :
// synopsys translate_on
load_cc ? alu_cc_lo[1] : ccm[1];
wire Cm
=
// synopsys translate_off
(load_cc===1'bx) ? 'bx :
// synopsys translate_on
load_cc ? alu_cc_lo[0] : ccm[0];
reg bicc_taken;
always @ (d_cond or Nm or Zm or Vm or Cm) begin
case (d_cond[2:0]) /* synopsys parallel_case */
3'b000: // BN
bicc_taken = 0;
3'b001: // BE
bicc_taken = Zm;
3'b010: // BLE
bicc_taken = Zm | (Nm ^ Vm);
3'b011: // BL
bicc_taken = Nm ^ Vm;
3'b100: // BLEU
bicc_taken = Cm | Zm;
3'b101: // BCS, GEU
bicc_taken = Cm;
3'b110: // BNEG
bicc_taken = Nm;
3'b111: // BVS
bicc_taken = Vm;
/* synopsys translate_off */
default:
bicc_taken = 'bx;
/* synopsys translate_on */
endcase
if(d_cond[3])
bicc_taken = ~bicc_taken;
end
endmodule
This page: |
Created: | Thu Aug 19 12:00:10 1999 |
| From: |
../../../sparc_v8/ssparc/iu/Mdecode/rtl/icceval.v
|