Date: Fri Aug 31 2007 - 01:15:42 PDT
Paul, The Verilog 1364-1995 LRM states that the vacated bit positions shall be filled with zeroes. So the effect of a shift larger than the size of the left operand is zero, independent of the shift direction. Cheers, Marq To verilog-ams <verilog-ams@server.eda-stds.org> Paul Floyd cc <Paul_Floyd@mentor.c om> Subject Shift limits Sent by: Classification owner-verilog-ams@se rver.eda.org 29-08-2007 17:38 Hi In the 2.2 LRM, section 4.1.10, no comment is made on the effect of a shift when the right operand is greater than the width of the left operand. In the ISO C standard, 1999, this is undefined (section 6.5.7, para 3; C is also undefined for a negative right operand whereas the Verilog-AMS LRM specifies that the right operand is treated as unsigned). Just a couple of examples: integer i, j; i = 1; j = i << 32; Is j undefined (like C) or 0? Same question for 'j = i >> 32;'. Regards Paul Floyd -- Dr. Paul Floyd Mentor Graphics Corporation -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.
