Mario1159/verilator
1
0
Fork 0
forked from github/verilator
Code Pull Requests Releases 1 Activity

Improve xor tree optimization (#4071)

Browse Source 
* AstNot does not have to be frozen in an xor tree during BitOp tree optimization.

* Tests: Update stats.
This commit is contained in:
Yutetsu TAKATSUKASA 2023-03-26 20:36:32 +09:00 committed by GitHub
parent 990b19e048
commit d4107dce52
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 2 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/V3Const.cpp
View File

@ -449,9 +449,7 @@ class ConstBitOpTreeVisitor final : public VNVisitorConst {
AstNode* lhsp = nodep->lhsp();
AstCCast* const castp = VN_CAST(lhsp, CCast);
if (castp) lhsp = castp->lhsp();
CONST_BITOP_RETURN_IF(!VN_IS(lhsp, VarRef) && !VN_IS(lhsp, Xor) && !VN_IS(lhsp, RedXor)
&& !VN_IS(lhsp, ShiftR),
lhsp);
CONST_BITOP_RETURN_IF(!isXorTree() && !VN_IS(lhsp, VarRef) && !VN_IS(lhsp, ShiftR), lhsp);
incrOps(nodep, __LINE__);
m_polarity = !m_polarity;
iterateChildrenConst(nodep);

2
test_regress/t/t_const_opt.pl
View File

@ -20,7 +20,7 @@ execute(
);
if ($Self->{vlt}) {
file_grep($Self->{stats}, qr/Optimizations, Const bit op reduction\s+(\d+)/i, 29);
file_grep($Self->{stats}, qr/Optimizations, Const bit op reduction\s+(\d+)/i, 39);
}
ok(1);
1;