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authorClifford Wolf <clifford@clifford.at>2013-11-08 04:44:09 +0100
committerClifford Wolf <clifford@clifford.at>2013-11-08 04:44:09 +0100
commit4abc8e695ad0b3b11ae687d776856dd98b56101d (patch)
tree4be3de49238ba12be945a756de5de0f18897cb31 /frontends/ast/simplify.cc
parent81b8f3292e997cc2fda5f3da63cbca2707936c35 (diff)
Implemented const folding of ternary op with undef select
Diffstat (limited to 'frontends/ast/simplify.cc')
-rw-r--r--frontends/ast/simplify.cc8
1 files changed, 8 insertions, 0 deletions
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 5c0130d4..9fa7f558 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -1074,6 +1074,14 @@ skip_dynamic_range_lvalue_expansion:;
if (choice != NULL && choice->type == AST_CONSTANT) {
RTLIL::Const y = choice->bitsAsConst(width_hint, sign_hint);
newNode = mkconst_bits(y.bits, sign_hint);
+ } else if (children[1]->type == AST_CONSTANT && children[2]->type == AST_CONSTANT) {
+ RTLIL::Const a = children[1]->bitsAsConst(width_hint, sign_hint);
+ RTLIL::Const b = children[2]->bitsAsConst(width_hint, sign_hint);
+ assert(a.bits.size() == b.bits.size());
+ for (size_t i = 0; i < a.bits.size(); i++)
+ if (a.bits[i] != b.bits[i])
+ a.bits[i] = RTLIL::State::Sx;
+ newNode = mkconst_bits(a.bits, sign_hint);
}
}
break;