From e46e7bbf99c375bd318c25f81f16e110606c80e4 Mon Sep 17 00:00:00 2001
From: Wilson Snyder <wsnyder@wsnyder.org>
Date: Wed, 12 Nov 2008 20:54:58 -0500
Subject: [PATCH] Fix 'bad select range' warning missing some cases, bug43.

---
 Changes                               |  4 +++
 src/V3Const.cpp                       |  1 +
 src/V3Width.cpp                       | 13 +++++--
 test_regress/t/t_select_bad_range2.pl | 19 ++++++++++
 test_regress/t/t_select_bad_range2.v  | 52 +++++++++++++++++++++++++++
 5 files changed, 87 insertions(+), 2 deletions(-)
 create mode 100755 test_regress/t/t_select_bad_range2.pl
 create mode 100644 test_regress/t/t_select_bad_range2.v

diff --git a/Changes b/Changes
index 61e8a9407..69505c813 100644
--- a/Changes
+++ b/Changes
@@ -3,6 +3,10 @@ Revision history for Verilator
 The contributors that suggested a given feature are shown in [].  [by ...]
 indicates the contributor was also the author of the fix; Thanks!
 
+* Verilator 3.68***
+
+**** Fix 'bad select range' warning missing some cases, bug43. [Lane Brooks]
+
 * Verilator 3.681 2008/11/12
 
 ***  Add SystemVerilog unique and priority case.
diff --git a/src/V3Const.cpp b/src/V3Const.cpp
index 11ea66fdf..d64143e98 100644
--- a/src/V3Const.cpp
+++ b/src/V3Const.cpp
@@ -222,6 +222,7 @@ private:
 		&& (!varp->rangep() || varp->msb())  // else it's non-resolvable parameterized
 		&& ( (  (nodep->msbConst() > varp->msbMaxSelect())
 			|| (nodep->lsbConst() > varp->msbMaxSelect())))) {
+		// See also warning in V3Width
 		nodep->v3error("Selection index out of range: "
 			       <<nodep->msbConst()<<":"<<nodep->lsbConst()
 			       <<" outside "<<varp->msbMaxSelect()<<":0"
diff --git a/src/V3Width.cpp b/src/V3Width.cpp
index b1aebb36f..6635b4bb7 100644
--- a/src/V3Width.cpp
+++ b/src/V3Width.cpp
@@ -302,13 +302,22 @@ private:
 	    int selwidth = V3Number::log2b(frommsb+1-1)+1;	// Width to address a bit
 	    nodep->fromp()->iterateAndNext(*this,WidthVP(selwidth,selwidth,BOTH).p());
 	    if (widthBad(nodep->lsbp(),selwidth,selwidth)
-		&& nodep->lsbp()->width()!=32)
+		&& nodep->lsbp()->width()!=32) {
 		nodep->v3warn(WIDTH,"Bit extraction of var["<<frommsb<<":"<<fromlsb<<"] requires "
 			      <<selwidth<<" bit index, not "
 			      <<nodep->lsbp()->width()
 			      <<(nodep->lsbp()->width()!=nodep->lsbp()->widthMin()
 				 ?" or "+cvtToStr(nodep->lsbp()->widthMin()):"")
 			      <<" bits.");
+	    }
+	    if (nodep->lsbp()->castConst() && nodep->msbConst() > frommsb) {
+		// See also warning in V3Const
+		// We need to check here, because the widthCheck may silently
+		// add another SEL which will loose the out-of-range check
+		nodep->v3error("Selection index out of range: "
+ 			       <<nodep->msbConst()<<":"<<nodep->lsbConst()
+			       <<" outside "<<frommsb<<":"<<fromlsb);
+	    }
 	    widthCheck(nodep,"Extract Range",nodep->lsbp(),selwidth,selwidth,true);
 	}
     }
@@ -909,7 +918,7 @@ bool WidthVisitor::fixAutoExtend (AstNode*& nodepr, int expWidth) {
 void WidthVisitor::widthCheck (AstNode* nodep, const char* side,
 			      AstNode* underp, int expWidth, int expWidthMin,
 			      bool ignoreWarn) {
-    //UINFO(0,"wchk "<<nodep<<endl<<"  "<<underp<<endl<<"  e"<<expWidth<<" m"<<expWidthMin<<" i"<<ignoreWarn<<endl);
+    //UINFO(9,"wchk "<<side<<endl<<"  "<<nodep<<endl<<"  "<<underp<<endl<<"  e"<<expWidth<<" m"<<expWidthMin<<" i"<<ignoreWarn<<endl);
     if (expWidthMin==0) expWidthMin = expWidth;
     bool bad = widthBad(underp,expWidth,expWidthMin);
     if (bad && fixAutoExtend(underp/*ref*/,expWidth)) bad=false;  // Changes underp
diff --git a/test_regress/t/t_select_bad_range2.pl b/test_regress/t/t_select_bad_range2.pl
new file mode 100755
index 000000000..c4dec149c
--- /dev/null
+++ b/test_regress/t/t_select_bad_range2.pl
@@ -0,0 +1,19 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# General Public License or the Perl Artistic License.
+
+compile (
+	 v_flags2 => ["--lint-only"],
+	 fails=>$Last_Self->{v3},
+	 expect=>
+'%Error: t/t_select_bad_range2.v:\d+: Selection index out of range: 3:2 outside 1:0
+%Error: Exiting due to.*',
+	 );
+
+ok(1);
+1;
+
diff --git a/test_regress/t/t_select_bad_range2.v b/test_regress/t/t_select_bad_range2.v
new file mode 100644
index 000000000..73486f83c
--- /dev/null
+++ b/test_regress/t/t_select_bad_range2.v
@@ -0,0 +1,52 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2008 by Wilson Snyder.
+
+module t (/*AUTOARG*/
+   // Inputs
+   clk
+   );
+   input clk;
+
+   reg [1:0] in;
+
+   /*AUTOWIRE*/
+   // Beginning of automatic wires (for undeclared instantiated-module outputs)
+   wire [1:0]		out10;			// From test of Test.v
+   wire [1:0]		out32;			// From test of Test.v
+   // End of automatics
+
+   Test test (/*AUTOINST*/
+	      // Outputs
+	      .out32			(out32[1:0]),
+	      .out10			(out10[1:0]),
+	      // Inputs
+	      .in			(in[1:0]));
+
+   // Test loop
+   always @ (posedge clk) begin
+      in <= in + 1;
+`ifdef TEST_VERBOSE
+      $write("[%0t] in=%d out32=%d out10=%d\n",$time, in, out32, out10);
+`endif
+      if (in==3) begin
+	 $write("*-* All Finished *-*\n");
+	 $finish;
+      end
+   end
+endmodule
+
+module Test (/*AUTOARG*/
+   // Outputs
+   out32, out10,
+   // Inputs
+   in
+   );
+   input  [1:0] in;
+   output [1:0] out32;
+   output [1:0] out10;
+
+   assign out32 = in[3:2];
+   assign out10 = in[1:0];
+endmodule