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| author | Clifford Wolf <clifford@clifford.at> | 2014-01-20 20:25:20 +0100 |
|---|---|---|
| committer | Clifford Wolf <clifford@clifford.at> | 2014-01-20 20:25:20 +0100 |
| commit | 88fbdd4916a9a9f491d22075b63beb676153c3d3 (patch) | |
| tree | 8b9fba068f056c82b7e1cbe80a56403b33c99f8a /frontends/ast/simplify.cc | |
| parent | 32a91458a7dde9994ca28ec635c1bec8fe20111b (diff) | |
| download | yosys-88fbdd4916a9a9f491d22075b63beb676153c3d3.tar.gz yosys-88fbdd4916a9a9f491d22075b63beb676153c3d3.tar.bz2 yosys-88fbdd4916a9a9f491d22075b63beb676153c3d3.zip | |
Fixed algorithmic complexity of AST simplification of long expressions
Diffstat (limited to 'frontends/ast/simplify.cc')
| -rw-r--r-- | frontends/ast/simplify.cc | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc index c266800e9..bd5da14e3 100644 --- a/frontends/ast/simplify.cc +++ b/frontends/ast/simplify.cc @@ -237,8 +237,8 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage, case AST_ASSIGN_EQ: case AST_ASSIGN_LE: case AST_ASSIGN: - while (children[0]->simplify(false, false, true, stage, -1, false) == true) { } - while (children[1]->simplify(false, false, false, stage, -1, false) == true) { } + while (!children[0]->basic_prep && children[0]->simplify(false, false, true, stage, -1, false) == true) { } + while (!children[1]->basic_prep && children[1]->simplify(false, false, false, stage, -1, false) == true) { } children[0]->detectSignWidth(backup_width_hint, backup_sign_hint); children[1]->detectSignWidth(width_hint, sign_hint); width_hint = std::max(width_hint, backup_width_hint); @@ -247,11 +247,11 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage, case AST_PARAMETER: case AST_LOCALPARAM: - while (children[0]->simplify(false, false, false, stage, -1, false) == true) { } + while (!children[0]->basic_prep && children[0]->simplify(false, false, false, stage, -1, false) == true) { } children[0]->detectSignWidth(width_hint, sign_hint); if (children.size() > 1) { assert(children[1]->type == AST_RANGE); - while (children[1]->simplify(false, false, false, stage, -1, false) == true) { } + while (!children[1]->basic_prep && children[1]->simplify(false, false, false, stage, -1, false) == true) { } if (!children[1]->range_valid) log_error("Non-constant width range on parameter decl at %s:%d.\n", filename.c_str(), linenum); width_hint = std::max(width_hint, children[1]->range_left - children[1]->range_right + 1); @@ -306,7 +306,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage, width_hint = -1; sign_hint = true; for (auto child : children) { - while (child->simplify(false, false, in_lvalue, stage, -1, false) == true) { } + while (!child->basic_prep && child->simplify(false, false, in_lvalue, stage, -1, false) == true) { } child->detectSignWidthWorker(width_hint, sign_hint); } reset_width_after_children = true; @@ -336,7 +336,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage, if (detect_width_simple && width_hint < 0) { for (auto child : children) - while (child->simplify(false, false, in_lvalue, stage, -1, false) == true) { } + while (!child->basic_prep && child->simplify(false, false, in_lvalue, stage, -1, false) == true) { } if (type == AST_REPLICATE) while (children[0]->simplify(true, false, in_lvalue, stage, -1, false) == true) { } detectSignWidth(width_hint, sign_hint); @@ -1425,6 +1425,9 @@ apply_newNode: did_something = true; } + if (!did_something) + basic_prep = true; + return did_something; } |