aboutsummaryrefslogtreecommitdiffstats
path: root/frontends/ast/simplify.cc
diff options
context:
space:
mode:
Diffstat (limited to 'frontends/ast/simplify.cc')
-rw-r--r--frontends/ast/simplify.cc128
1 files changed, 108 insertions, 20 deletions
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 372dcf95c..837c14ad7 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -64,6 +64,21 @@ std::string AstNode::process_format_str(const std::string &sformat, int next_arg
continue;
}
+ bool got_len = false;
+ bool got_zlen = false;
+ int len_value = 0;
+
+ while ('0' <= cformat && cformat <= '9')
+ {
+ if (!got_len && cformat == '0')
+ got_zlen = true;
+
+ got_len = true;
+ len_value = 10*len_value + (cformat - '0');
+
+ cformat = sformat[++i];
+ }
+
// Simplify the argument
AstNode *node_arg = nullptr;
@@ -74,6 +89,9 @@ std::string AstNode::process_format_str(const std::string &sformat, int next_arg
case 'S':
case 'd':
case 'D':
+ if (got_len)
+ goto unsupported_format;
+ /* fall through */
case 'x':
case 'X':
if (next_arg >= GetSize(children))
@@ -88,9 +106,12 @@ std::string AstNode::process_format_str(const std::string &sformat, int next_arg
case 'm':
case 'M':
+ if (got_len)
+ goto unsupported_format;
break;
default:
+ unsupported_format:
log_file_error(filename, location.first_line, "System task `%s' called with invalid/unsupported format specifier.\n", str.c_str());
break;
}
@@ -104,19 +125,28 @@ std::string AstNode::process_format_str(const std::string &sformat, int next_arg
case 'd':
case 'D':
- {
- char tmp[128];
- snprintf(tmp, sizeof(tmp), "%d", node_arg->bitsAsConst().as_int());
- sout += tmp;
- }
+ sout += stringf("%d", node_arg->bitsAsConst().as_int());
break;
case 'x':
case 'X':
{
- char tmp[128];
- snprintf(tmp, sizeof(tmp), "%x", node_arg->bitsAsConst().as_int());
- sout += tmp;
+ Const val = node_arg->bitsAsConst();
+
+ while (GetSize(val) % 4 != 0)
+ val.bits.push_back(State::S0);
+
+ int len = GetSize(val) / 4;
+ for (int i = len; i < len_value; i++)
+ sout += got_zlen ? '0' : ' ';
+
+ for (int i = len-1; i >= 0; i--) {
+ Const digit = val.extract(4*i, 4);
+ if (digit.is_fully_def())
+ sout += stringf(cformat == 'x' ? "%x" : "%X", digit.as_int());
+ else
+ sout += cformat == 'x' ? "x" : "X";
+ }
}
break;
@@ -1724,8 +1754,10 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
}
// replace dynamic ranges in left-hand side expressions (e.g. "foo[bar] <= 1'b1;") with
- // a big case block that selects the correct single-bit assignment.
- if (type == AST_ASSIGN_EQ || type == AST_ASSIGN_LE) {
+ // either a big case block that selects the correct single-bit assignment, or mask and
+ // shift operations.
+ if (type == AST_ASSIGN_EQ || type == AST_ASSIGN_LE)
+ {
if (children[0]->type != AST_IDENTIFIER || children[0]->children.size() == 0)
goto skip_dynamic_range_lvalue_expansion;
if (children[0]->children[0]->range_valid || did_something)
@@ -1734,10 +1766,13 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
goto skip_dynamic_range_lvalue_expansion;
if (!children[0]->id2ast->range_valid)
goto skip_dynamic_range_lvalue_expansion;
+
int source_width = children[0]->id2ast->range_left - children[0]->id2ast->range_right + 1;
int result_width = 1;
+
AstNode *shift_expr = NULL;
AstNode *range = children[0]->children[0];
+
if (range->children.size() == 1) {
shift_expr = range->children[0]->clone();
} else {
@@ -1750,19 +1785,72 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
log_file_error(filename, location.first_line, "Unsupported expression on dynamic range select on signal `%s'!\n", str.c_str());
result_width = abs(int(left_at_zero_ast->integer - right_at_zero_ast->integer)) + 1;
}
- did_something = true;
- newNode = new AstNode(AST_CASE, shift_expr);
- for (int i = 0; i < source_width; i++) {
- int start_bit = children[0]->id2ast->range_right + i;
- AstNode *cond = new AstNode(AST_COND, mkconst_int(start_bit, true));
+
+ if (0)
+ {
+ // big case block
+
+ did_something = true;
+ newNode = new AstNode(AST_CASE, shift_expr);
+ for (int i = 0; i < source_width; i++) {
+ int start_bit = children[0]->id2ast->range_right + i;
+ AstNode *cond = new AstNode(AST_COND, mkconst_int(start_bit, true));
+ AstNode *lvalue = children[0]->clone();
+ lvalue->delete_children();
+ int end_bit = std::min(start_bit+result_width,source_width) - 1;
+ lvalue->children.push_back(new AstNode(AST_RANGE,
+ mkconst_int(end_bit, true), mkconst_int(start_bit, true)));
+ cond->children.push_back(new AstNode(AST_BLOCK, new AstNode(type, lvalue, children[1]->clone())));
+ newNode->children.push_back(cond);
+ }
+ }
+ else
+ {
+ // mask and shift operations, disabled for now
+
+ AstNode *wire_mask = new AstNode(AST_WIRE, new AstNode(AST_RANGE, mkconst_int(source_width-1, true), mkconst_int(0, true)));
+ wire_mask->str = stringf("$bitselwrite$mask$%s:%d$%d", filename.c_str(), location.first_line, autoidx++);
+ wire_mask->attributes["\\nosync"] = AstNode::mkconst_int(1, false);
+ wire_mask->is_logic = true;
+ while (wire_mask->simplify(true, false, false, 1, -1, false, false)) { }
+ current_ast_mod->children.push_back(wire_mask);
+
+ AstNode *wire_data = new AstNode(AST_WIRE, new AstNode(AST_RANGE, mkconst_int(source_width-1, true), mkconst_int(0, true)));
+ wire_data->str = stringf("$bitselwrite$data$%s:%d$%d", filename.c_str(), location.first_line, autoidx++);
+ wire_data->attributes["\\nosync"] = AstNode::mkconst_int(1, false);
+ wire_data->is_logic = true;
+ while (wire_data->simplify(true, false, false, 1, -1, false, false)) { }
+ current_ast_mod->children.push_back(wire_data);
+
+ did_something = true;
+ newNode = new AstNode(AST_BLOCK);
+
AstNode *lvalue = children[0]->clone();
lvalue->delete_children();
- int end_bit = std::min(start_bit+result_width,source_width) - 1;
- lvalue->children.push_back(new AstNode(AST_RANGE,
- mkconst_int(end_bit, true), mkconst_int(start_bit, true)));
- cond->children.push_back(new AstNode(AST_BLOCK, new AstNode(type, lvalue, children[1]->clone())));
- newNode->children.push_back(cond);
+
+ AstNode *ref_mask = new AstNode(AST_IDENTIFIER);
+ ref_mask->str = wire_mask->str;
+ ref_mask->id2ast = wire_mask;
+ ref_mask->was_checked = true;
+
+ AstNode *ref_data = new AstNode(AST_IDENTIFIER);
+ ref_data->str = wire_data->str;
+ ref_data->id2ast = wire_data;
+ ref_data->was_checked = true;
+
+ AstNode *old_data = lvalue->clone();
+ if (type == AST_ASSIGN_LE)
+ old_data->lookahead = true;
+
+ AstNode *shamt = shift_expr;
+
+ newNode->children.push_back(new AstNode(AST_ASSIGN_EQ, ref_mask->clone(),
+ new AstNode(AST_SHIFT_LEFT, mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false), shamt->clone())));
+ newNode->children.push_back(new AstNode(AST_ASSIGN_EQ, ref_data->clone(),
+ new AstNode(AST_SHIFT_LEFT, new AstNode(AST_BIT_AND, mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false), children[1]->clone()), shamt)));
+ newNode->children.push_back(new AstNode(type, lvalue, new AstNode(AST_BIT_OR, new AstNode(AST_BIT_AND, old_data, new AstNode(AST_BIT_NOT, ref_mask)), ref_data)));
}
+
goto apply_newNode;
}
skip_dynamic_range_lvalue_expansion:;
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-04 10:10:57 +0000