RE: [sv-bc] D3 5.7.1: default length of x/z

From: Chris Spear <Chris.Spear_at_.....>
Date: Mon May 28 2007 - 05:49:04 PDT
  

Shalom,

'hz and 'hx are treated as 32-bit numbers. But unlike 'h0 and 'h1, the z
or x values are extended into the upper bits.  So 'hz is equivalent to
32'hZZZZ_ZZZZ and 32'hx is equivalent to 32'hXXXX_XXXX.

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________________________________

From: owner-sv-bc@eda.org [mailto:owner-sv-bc@eda.org] On Behalf Of
Bresticker, Shalom
Sent: Monday, May 28, 2007 4:51 AM
To: sv-bc@eda.org
Subject: [sv-bc] D3 5.7.1: default length of x/z

 

Hi,

In Draft 3, 5.7.1 says,

"The default length of x and z is the same as the default length of an
integer."

This sentence goes back to 1364.

My question is, what is meant by "x and z" here?

x and z, unlike a simple integer like "3", cannot appear in the simple
forms "x" and "z".

Then they would be treated as identifiers, data object names.

Is it referring to forms like 'hx, 'bz?

If so, we already have a sentence that says,

"The number of bits that make up an unsized number (which is a simple
decimal number or a number with a base specifier but no size
specification) shall be at least 32." 

The sentence is currently misleading as it could refer to forms like 'x,
which when self-determined is 1 bit, not 32 bits.

Also, the word "integer" in the sentence is also ambiguous, as there are
many types of integers. For example, 1'b0 is also an integer. It is a
sized integer constant.

Shalom

Shalom Bresticker

Intel Jerusalem LAD DA

+972 2 589-6852

+972 54 721-1033 

 


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Received on Mon May 28 05:51:40 2007

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