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-rw-r--r--frontends/ast/simplify.cc85
1 files changed, 73 insertions, 12 deletions
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 252219094..3314819fb 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -91,7 +91,7 @@ std::string AstNode::process_format_str(const std::string &sformat, int next_arg
case 'D':
if (got_len)
goto unsupported_format;
- /* fall through */
+ YS_FALLTHROUGH
case 'x':
case 'X':
if (next_arg >= GetSize(children))
@@ -608,6 +608,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
case AST_TO_BITS:
case AST_TO_SIGNED:
case AST_TO_UNSIGNED:
+ case AST_SELFSZ:
case AST_CONCAT:
case AST_REPLICATE:
case AST_REDUCE_AND:
@@ -1079,7 +1080,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
}
if (old_range_valid != range_valid)
did_something = true;
- if (range_valid && range_left >= 0 && range_right > range_left) {
+ if (range_valid && range_right > range_left) {
int tmp = range_right;
range_right = range_left;
range_left = tmp;
@@ -1097,6 +1098,25 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
range_swapped = children[0]->range_swapped;
range_left = children[0]->range_left;
range_right = children[0]->range_right;
+ bool force_upto = false, force_downto = false;
+ if (attributes.count(ID::force_upto)) {
+ AstNode *val = attributes[ID::force_upto];
+ if (val->type != AST_CONSTANT)
+ log_file_error(filename, location.first_line, "Attribute `force_upto' with non-constant value!\n");
+ force_upto = val->asAttrConst().as_bool();
+ }
+ if (attributes.count(ID::force_downto)) {
+ AstNode *val = attributes[ID::force_downto];
+ if (val->type != AST_CONSTANT)
+ log_file_error(filename, location.first_line, "Attribute `force_downto' with non-constant value!\n");
+ force_downto = val->asAttrConst().as_bool();
+ }
+ if (force_upto && force_downto)
+ log_file_error(filename, location.first_line, "Attributes `force_downto' and `force_upto' cannot be both set!\n");
+ if ((force_upto && !range_swapped) || (force_downto && range_swapped)) {
+ std::swap(range_left, range_right);
+ range_swapped = force_upto;
+ }
}
} else {
if (!range_valid)
@@ -1788,7 +1808,18 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
result_width = abs(int(left_at_zero_ast->integer - right_at_zero_ast->integer)) + 1;
}
- if (0)
+ bool use_case_method = false;
+
+ if (children[0]->id2ast->attributes.count(ID::nowrshmsk)) {
+ AstNode *node = children[0]->id2ast->attributes.at(ID::nowrshmsk);
+ while (node->simplify(true, false, false, stage, -1, false, false)) { }
+ if (node->type != AST_CONSTANT)
+ log_file_error(filename, location.first_line, "Non-constant value for `nowrshmsk' attribute on `%s'!\n", children[0]->id2ast->str.c_str());
+ if (node->asAttrConst().as_bool())
+ use_case_method = true;
+ }
+
+ if (use_case_method)
{
// big case block
@@ -1796,10 +1827,10 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
newNode = new AstNode(AST_CASE, shift_expr);
for (int i = 0; i < source_width; i++) {
int start_bit = children[0]->id2ast->range_right + i;
+ int end_bit = std::min(start_bit+result_width,source_width) - 1;
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())));
@@ -1846,11 +1877,40 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
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)));
+ int shamt_width_hint = 0;
+ bool shamt_sign_hint = true;
+ shamt->detectSignWidth(shamt_width_hint, shamt_sign_hint);
+
+ int start_bit = children[0]->id2ast->range_right;
+ bool use_shift = shamt_sign_hint;
+
+ if (start_bit != 0) {
+ shamt = new AstNode(AST_SUB, shamt, mkconst_int(start_bit, true));
+ use_shift = true;
+ }
+
+ AstNode *t;
+
+ t = mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false);
+ if (use_shift)
+ t = new AstNode(AST_SHIFT, t, new AstNode(AST_NEG, shamt->clone()));
+ else
+ t = new AstNode(AST_SHIFT_LEFT, t, shamt->clone());
+ t = new AstNode(AST_ASSIGN_EQ, ref_mask->clone(), t);
+ newNode->children.push_back(t);
+
+ t = new AstNode(AST_BIT_AND, mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false), children[1]->clone());
+ if (use_shift)
+ t = new AstNode(AST_SHIFT, t, new AstNode(AST_NEG, shamt));
+ else
+ t = new AstNode(AST_SHIFT_LEFT, t, shamt);
+ t = new AstNode(AST_ASSIGN_EQ, ref_data->clone(), t);
+ newNode->children.push_back(t);
+
+ t = new AstNode(AST_BIT_AND, old_data, new AstNode(AST_BIT_NOT, ref_mask));
+ t = new AstNode(AST_BIT_OR, t, ref_data);
+ t = new AstNode(type, lvalue, t);
+ newNode->children.push_back(t);
}
goto apply_newNode;
@@ -3026,6 +3086,7 @@ replace_fcall_later:;
}
}
break;
+ if (0) { case AST_SELFSZ: const_func = RTLIL::const_pos; }
if (0) { case AST_POS: const_func = RTLIL::const_pos; }
if (0) { case AST_NEG: const_func = RTLIL::const_neg; }
if (children[0]->type == AST_CONSTANT) {
@@ -3034,10 +3095,10 @@ replace_fcall_later:;
} else
if (children[0]->isConst()) {
newNode = new AstNode(AST_REALVALUE);
- if (type == AST_POS)
- newNode->realvalue = +children[0]->asReal(sign_hint);
- else
+ if (type == AST_NEG)
newNode->realvalue = -children[0]->asReal(sign_hint);
+ else
+ newNode->realvalue = +children[0]->asReal(sign_hint);
}
break;
case AST_TERNARY:
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-06 21:07:06 +0000