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Fix up parameter name part select 

Part select of parameter names is fixed up to be structurally similar
to part select of signals, and also to behave similarly. (Though not
identically, for reason.)
This commit is contained in:
Stephen Williams 2008-06-08 07:34:45 -07:00
parent b31124983a
commit 7aebff2a86
2 changed files with 114 additions and 70 deletions
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10
PExpr.h
View File

@ -306,6 +306,10 @@ class PEIdent : public PExpr {
private:
// Common functions to calculate parts of part/bit selects.
bool calculate_parts_(Design*, NetScope*, long&msb, long&lsb) const;
bool calculate_param_range_(Design*, NetScope*,
const NetExpr*msb_ex, long&msb,
const NetExpr*lsb_ex, long&lsb) const;
bool calculate_up_do_width_(Design*, NetScope*, unsigned long&wid) const;
private:
@ -321,6 +325,12 @@ class PEIdent : public PExpr {
NetScope*found,
const NetExpr*par_msb,
const NetExpr*par_lsb) const;
NetExpr*elaborate_expr_param_part_(Design*des,
NetScope*scope,
const NetExpr*par,
NetScope*found,
const NetExpr*par_msb,
const NetExpr*par_lsb) const;
NetExpr*elaborate_expr_net(Design*des,
NetScope*scope,
NetNet*net,

174
elab_expr.cc
View File

@ -882,6 +882,34 @@ bool PEIdent::calculate_up_do_width_(Design*des, NetScope*scope,
return flag;
}
bool PEIdent::calculate_param_range_(Design*des, NetScope*scope,
const NetExpr*par_msb, long&par_msv,
const NetExpr*par_lsb, long&par_lsv) const
{
if (par_msb == 0) {
// If the parameter doesn't have an explicit range, then
// just return range values of 0:0. The par_msv==0 is
// correct. The par_msv is not necessarily correct, but
// clients of this function don't need a correct value.
ivl_assert(*this, par_lsb == 0);
par_msv = 0;
par_lsv = 0;
return true;
}
const NetEConst*tmp = dynamic_cast<const NetEConst*> (par_msb);
ivl_assert(*this, tmp);
par_msv = tmp->value().as_long();
tmp = dynamic_cast<const NetEConst*> (par_lsb);
ivl_assert(*this, tmp);
par_lsv = tmp->value().as_long();
return true;
}
unsigned PEIdent::test_width(Design*des, NetScope*scope,
unsigned min, unsigned lval,
bool&unsized_flag) const
@ -1094,6 +1122,71 @@ NetExpr* PEIdent::elaborate_expr(Design*des, NetScope*scope,
return 0;
}
NetExpr* PEIdent::elaborate_expr_param_part_(Design*des, NetScope*scope,
const NetExpr*par,
NetScope*found_in,
const NetExpr*par_msb,
const NetExpr*par_lsb) const
{
long msv, lsv;
bool flag = calculate_parts_(des, scope, msv, lsv);
if (!flag)
return 0;
long par_msv, par_lsv;
flag = calculate_param_range_(des, scope, par_msb, par_msv, par_lsb, par_lsv);
if (!flag)
return 0;
// Notice that the par_msv is not used is this function other
// then for this test. It is used to tell the direction that
// the bits are numbers, so that we can make sure the
// direction matches the part select direction. After that,
// we only need the par_lsv.
if (msv>lsv && par_msv<par_lsv || msv<lsv && par_msv>=par_lsv) {
cerr << get_fileline() << ": error: Part select "
<< "[" << msv << ":" << lsv << "] is out of order." << endl;
des->errors += 1;
return 0;
}
long wid = 1 + labs(msv-lsv);
if (debug_elaborate)
cerr << get_fileline() << ": debug: Calculate part select "
<< "[" << msv << ":" << lsv << "] from range "
<< "[" << par_msv << ":" << par_lsv << "]." << endl;
verinum result (verinum::Vx, wid, true);
const NetEConst*par_ex = dynamic_cast<const NetEConst*> (par);
ivl_assert(*this, par_ex);
verinum par_val = par_ex->value();
for (long idx = 0 ; idx < wid ; idx += 1) {
long off = idx + lsv - par_lsv;
if (off < 0)
result.set(idx, verinum::Vx);
else if (off < (long)par_val.len())
result.set(idx, par_val.get(off));
else if (par_val.is_string()) // Pad strings with nulls.
result.set(idx, verinum::V0);
else if (par_val.has_len()) // Pad sized parameters with X
result.set(idx, verinum::Vx);
else // Unsized parameters are "infinite" width.
result.set(idx, sign_bit(par_val));
}
// If the input is a string, and the part select is working on
// byte boundaries, then make the result into a string.
if (par_val.is_string() && (labs(lsv-par_lsv)%8 == 0) && (wid%8 == 0))
result = verinum(result.as_string());
NetEConst*result_ex = new NetEConst(result);
result_ex->set_line(*this);
return result_ex;
}
/*
* Handle the case that the identifier is a parameter reference. The
* parameter expression has already been located for us (as the par
@ -1106,84 +1199,25 @@ NetExpr* PEIdent::elaborate_expr_param(Design*des,
const NetExpr*par_msb,
const NetExpr*par_lsb) const
{
NetExpr*tmp = par->dup_expr();
const name_component_t&name_tail = path_.back();
index_component_t::ctype_t use_sel = index_component_t::SEL_NONE;
if (!name_tail.index.empty())
use_sel = name_tail.index.back().sel;
if (use_sel == index_component_t::SEL_PART) {
ivl_assert(*this, !name_tail.index.empty());
const index_component_t&index_tail = name_tail.index.back();
ivl_assert(*this, index_tail.msb);
ivl_assert(*this, index_tail.lsb);
// NOTE TO SELF: This is the way I want to see this code
// structured. This closely follows the structure of the
// elaborate_expr_net_ code, which splits all the various
// selects to different methods.
if (use_sel == index_component_t::SEL_PART)
return elaborate_expr_param_part_(des, scope, par, found_in,
par_msb, par_lsb);
/* If the identifier has a part select, we support
it by pulling the right bits out and making a
sized unsigned constant. This code assumes the
lsb of a parameter is 0 and the msb is the
width of the parameter. */
// NOTE TO SELF (continued): The code below should be
// rewritten in the above format, as I get to it.
verinum*lsn = index_tail.lsb->eval_const(des, scope);
verinum*msn = index_tail.msb->eval_const(des, scope);
if ((lsn == 0) || (msn == 0)) {
cerr << get_fileline() << ": error: "
"Part select expressions must be "
"constant expressions." << endl;
des->errors += 1;
return 0;
}
NetExpr*tmp = par->dup_expr();
long lsb = lsn->as_long();
long msb = msn->as_long();
if ((lsb < 0) || (msb < lsb)) {
cerr << get_fileline() << ": error: invalid part "
<< "select: " << path_
<< "["<<msb<<":"<<lsb<<"]" << endl;
des->errors += 1;
return 0;
}
unsigned long ulsb=lsb;
unsigned long umsb=msb;
NetEConst*le = dynamic_cast<NetEConst*>(tmp);
assert(le);
verinum result (verinum::V0, msb-lsb+1, true);
verinum exl = le->value();
/* Pull the bits from the parameter, one at a
time. If the bit is within the range, simply
copy it to the result. If the bit is outside
the range, we sign extend signed unsized
numbers, zero extend unsigned unsigned numbers,
and X extend sized numbers. */
for (unsigned long idx = ulsb ; idx <= umsb ; idx += 1) {
if (idx < exl.len())
result.set(idx-lsb, exl.get(idx));
else if (exl.is_string())
result.set(idx-lsb, verinum::V0);
else if (exl.has_len())
result.set(idx-lsb, verinum::Vx);
else if (exl.has_sign())
result.set(idx-lsb, exl.get(exl.len()-1));
else
result.set(idx-lsb, verinum::V0);
}
/* If the input is a string, and the part select
is working on byte boundaries, then the result
can be made into a string. */
if (exl.is_string()
&& (lsb%8 == 0)
&& (result.len()%8 == 0))
result = verinum(result.as_string());
delete tmp;
tmp = new NetEConst(result);
} else if (use_sel == index_component_t::SEL_IDX_UP || use_sel == index_component_t::SEL_IDX_DO) {
if (use_sel == index_component_t::SEL_IDX_UP || use_sel == index_component_t::SEL_IDX_DO) {
ivl_assert(*this, !name_tail.index.empty());
const index_component_t&index_tail = name_tail.index.back();