Use proper bit width ans sign extension for const folding

diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index e5cc7c4cc74656a3a78c715c8faa3069d285d7b7..cc65658c809df858b5d9fc3ab60756697edc2fc1 100644 (file)
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -950,8 +950,8 @@ skip_dynamic_range_lvalue_expansion:;
                        break;
                case AST_BIT_NOT:
                        if (children[0]->type == AST_CONSTANT) {
-                               RTLIL::Const y = RTLIL::const_not(RTLIL::Const(children[0]->bits), dummy_arg, children[0]->is_signed, false, -1);
-                               newNode = mkconst_bits(y.bits, false);
+                               RTLIL::Const y = RTLIL::const_not(children[0]->bitsAsConst(width_hint, sign_hint), dummy_arg, sign_hint, false, width_hint);
+                               newNode = mkconst_bits(y.bits, sign_hint);
                        }
                        break;
                if (0) { case AST_BIT_AND:  const_func = RTLIL::const_and;  }
@@ -959,9 +959,9 @@ skip_dynamic_range_lvalue_expansion:;
                if (0) { case AST_BIT_XOR:  const_func = RTLIL::const_xor;  }
                if (0) { case AST_BIT_XNOR: const_func = RTLIL::const_xnor; }
                        if (children[0]->type == AST_CONSTANT && children[1]->type == AST_CONSTANT) {
-                               RTLIL::Const y = const_func(RTLIL::Const(children[0]->bits), RTLIL::Const(children[1]->bits),
-                                               children[0]->is_signed, children[1]->is_signed, -1);
-                               newNode = mkconst_bits(y.bits, false);
+                               RTLIL::Const y = const_func(children[0]->bitsAsConst(width_hint, sign_hint),
+                                               children[1]->bitsAsConst(width_hint, sign_hint), sign_hint, sign_hint, width_hint);
+                               newNode = mkconst_bits(y.bits, sign_hint);
                        }
                        break;
                if (0) { case AST_REDUCE_AND:  const_func = RTLIL::const_reduce_and;  }
@@ -970,7 +970,7 @@ skip_dynamic_range_lvalue_expansion:;
                if (0) { case AST_REDUCE_XNOR: const_func = RTLIL::const_reduce_xnor; }
                if (0) { case AST_REDUCE_BOOL: const_func = RTLIL::const_reduce_bool; }
                        if (children[0]->type == AST_CONSTANT) {
-                               RTLIL::Const y = const_func(RTLIL::Const(children[0]->bits), dummy_arg, children[0]->is_signed, false, -1);
+                               RTLIL::Const y = const_func(RTLIL::Const(children[0]->bits), dummy_arg, false, false, -1);
                                newNode = mkconst_bits(y.bits, false);
                        }
                        break;
@@ -993,8 +993,9 @@ skip_dynamic_range_lvalue_expansion:;
                if (0) { case AST_SHIFT_SLEFT:  const_func = RTLIL::const_sshl; }
                if (0) { case AST_SHIFT_SRIGHT: const_func = RTLIL::const_sshr; }
                        if (children[0]->type == AST_CONSTANT && children[1]->type == AST_CONSTANT) {
-                               RTLIL::Const y = const_func(RTLIL::Const(children[0]->bits), RTLIL::Const(children[1]->bits), children[0]->is_signed, false, -1);
-                               newNode = mkconst_bits(y.bits, children[0]->is_signed);
+                               RTLIL::Const y = const_func(children[0]->bitsAsConst(width_hint, sign_hint),
+                                               RTLIL::Const(children[1]->bits), sign_hint, false, width_hint);
+                               newNode = mkconst_bits(y.bits, sign_hint);
                        }
                        break;
                if (0) { case AST_LT: const_func = RTLIL::const_lt; }
@@ -1004,8 +1005,10 @@ skip_dynamic_range_lvalue_expansion:;
                if (0) { case AST_GE: const_func = RTLIL::const_ge; }
                if (0) { case AST_GT: const_func = RTLIL::const_gt; }
                        if (children[0]->type == AST_CONSTANT && children[1]->type == AST_CONSTANT) {
-                               RTLIL::Const y = const_func(RTLIL::Const(children[0]->bits), RTLIL::Const(children[1]->bits),
-                                               children[0]->is_signed, children[1]->is_signed, -1);
+                               int cmp_width = std::max(children[0]->bits.size(), children[1]->bits.size());
+                               bool cmp_signed = children[0]->is_signed && children[1]->is_signed;
+                               RTLIL::Const y = const_func(children[0]->bitsAsConst(cmp_width, cmp_signed),
+                                               children[1]->bitsAsConst(cmp_width, cmp_signed), cmp_signed, cmp_signed, 1);
                                newNode = mkconst_bits(y.bits, false);
                        }
                        break;
@@ -1016,18 +1019,16 @@ skip_dynamic_range_lvalue_expansion:;
                if (0) { case AST_MOD: const_func = RTLIL::const_mod; }
                if (0) { case AST_POW: const_func = RTLIL::const_pow; }
                        if (children[0]->type == AST_CONSTANT && children[1]->type == AST_CONSTANT) {
-                               RTLIL::Const y = const_func(RTLIL::Const(children[0]->bits), RTLIL::Const(children[1]->bits),
-                                               children[0]->is_signed, children[1]->is_signed, -1);
-                               newNode = mkconst_bits(y.bits, children[0]->is_signed && children[1]->is_signed);
+                               RTLIL::Const y = const_func(children[0]->bitsAsConst(width_hint, sign_hint),
+                                               children[1]->bitsAsConst(width_hint, sign_hint), sign_hint, sign_hint, width_hint);
+                               newNode = mkconst_bits(y.bits, sign_hint);
                        }
                        break;
                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) {
-                               RTLIL::Const y = const_func(RTLIL::Const(children[0]->bits), dummy_arg, children[0]->is_signed, false, -1);
-                               newNode = mkconst_bits(y.bits, children[0]->is_signed);
-                               // RTLIL::Const y = const_func(children[0]->bitsAsConst(width_hint), dummy_arg, sign_hint, false, width_hint);
-                               // newNode = mkconst_bits(y.bits, sign_hint);
+                               RTLIL::Const y = const_func(children[0]->bitsAsConst(width_hint, sign_hint), dummy_arg, sign_hint, false, width_hint);
+                               newNode = mkconst_bits(y.bits, sign_hint);
                        }
                        break;
                case AST_TERNARY: