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Re: [PATCH, middle-end]: Fix PR tree-optimization/{31966, 32533}

On 7/2/07, Uros Bizjak <> wrote:

As described in great detail in PR 31966, Comment #7 and Comment #6,
there is a nasty bug in tree-if-convert.c. When a bb with condition
code directly feeds bb with a phi node, current implementation
"forgets" to account for the condition for the branch that leads to
the phi node [see PR for further explanation and for the proof].

The patch fixes this by attaching a condition of true or false arm to
relevant edge. When constructing equivalent condition for phi node,
incoming edges are checked if there is a condition attached to them,
and in this case equivalent condition is constructed by boolean AND of
successor block predicate and edge condition.

The patch has been checked on i686-pc-linux-gnu on  gcc-41 and gcc-42
branches, as well as mainline, for all default languages. It fixes two
PRs and (as reported in PR32533) fixes a bunch of failing CP2K

OK for mainline and 4.1 and 4.2 branch?

This is ok. Please let it have a few days on mainline before committing to the branches.


2007-07-02 Uros Bizjak <>

        PR tree-optimization/31966
        PR tree-optimization/32533
        * tree-if-conv.c (add_to_dst_predicate_list): Use "edge", not
        "basic_block" description as its third argument.  Update function
        calls to get destination bb from "edge" argument.  Save "cond" into
        aux field of the edge.  Update prototype for changed arguments.
        (find_phi_replacement_condition): Operate on incoming edges, not
        on predecessor blocks.  If there is a condition saved in the
        incoming edge aux field, AND it with incoming bb predicate.
        Return source bb of the first edge.
        (clean_predicate_lists): Clean aux field of outgoing node edges.
        (tree_if_conversion): Do not initialize cond variable. Move
        variable declaration into the loop.
        (replace_phi_with_cond_gimple_modify_stmt): Remove unneded
        initializations of new_stmt, arg0 and arg1 variables.


2007-07-02 Uros Bizjak <>

        PR tree-optimization/31966
        PR tree-optimization/32533
        * gcc.dg/tree-ssa/pr31966.c: New runtime test.
        * gfortran.dg/pr32533.f90: Ditto.


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