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Re: [tree-ssa] New regressions as of 2003-11-04

In message <>, Zdenek Dvorak wri
 >>  >Yes; the statement insertion/removal updates this mapping (but just for
 >>  >sure I will create a patch that adds a test for this to
 >>  >tree_verify_flow_info).
 >> Excellent.
 >> I just remembered the other concern I had when I first looked at the
 >> patch.  Can't a VAR_DECL or PARM_DECL be changed by an ASM_EXPR, 
 >> CALL_EXPR and possibly other nodes?   It seems to me that the test
 >> for invalidating the var needs to be a lot more aggressive.
 >Due to this check
 >+         if (!ann
 >+             || ann->may_aliases
 >+             || TREE_ADDRESSABLE (var))
 >+           var = NULL_TREE;
 >it should be safe against CALL_EXPRs (I hope).
Ah yes.

 > I am not quite sure about ASM_EXPRs.
I think VA_ARG_EXPR is also problematical since it modifies its argument
and can appear on the RHS of a statement as well.  Ugh.

You might just want to punt those cases
if (TREE_CODE (stmt) == ASM_EXPR
    || TREE_CODE (stmt) == VA_ARG_EXPR
    || (TREE_CODE (stmt) == MODIFY_EXPR
        && TREE_CODE (TREE_OPERAND (stmt, 1)) == VA_ARG_EXPR))
  invalidate var

Or something close to that.

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