On Sat, Sep 24, 2011 at 6:41 PM, Eric Botcazou <ebotca...@adacore.com> wrote: > Hi, > > this is a couple of small tweaks to the GIMPLE optimizers aimed at helping > vectorization in Ada. More changes will be needed, so no testcases yet. > > > 1. pass_fold_builtins knows how to delete a call to __builtin_stack_restore > that is the only real statement in a cleanup, i.e. to turn > > <L101>: > .builtin_stack_restore (saved_stack.116_22); > resx 1 > > into > > <L101>: > GIMPLE_NOP > resx 1 > > This is valid when the block has no outgoing edge. Then ehcleanup can in turn > delete the cleanup as empty. The problem is that pass_fold_builtins runs very > late in the game, so most of the optimizations, e.g. vectorization, are > constrained by the EH structure, all the more so if -fnon-call-exceptions is > enabled like in Ada. This happens as soon as you do dynamic stack allocation, > because then you have a call to __builtin_stack_restore in the FINALLY part of > a TRY-FINALLY structure, hence the cleanup. > > The first change enhances ehcleanup so as to remove this kind of cleanups on > its own, without the need to wait for pass_fold_builtins. > > > 2. The introduction of MEM_REF has disabled vectorization for parameters > passed by reference in Ada. This used to work because dr_analyze_innermost > was always building a pointer via build_fold_addr_expr; now, if the base is a > MEM_REF, it can just take the first operand, which is a reference and not a > pointer for a parameter passed by reference in Ada. And simple_iv, unlike > other functions in tree-scalar-evolution.c, accepts only pointer types: > > type = TREE_TYPE (op); > if (TREE_CODE (type) != INTEGER_TYPE > && TREE_CODE (type) != POINTER_TYPE) > return false; > > The second change makes simple_iv use the same test as the other functions in > tree-scalar-evolution.c. > > > Bootstrapped/regtested on x86_64-suse-linux, OK for mainline?
Use gimple_call_builtin_p (stmt, BUILT_IN_STACK_RESTORE) instead of re-inventing it with is_gimple_stack_restore. Otherwise ok. Thanks, Richard. > > > 2011-09-24 Eric Botcazou <ebotca...@adacore.com> > > * tree-eh.c (is_gimple_stack_restore): New predicate. > (cleanup_empty_eh): Allow a call to __builtin_stack_restore if there > is no outgoing edge. > > * tree-scalar-evolution.c (simple_iv): Accept all pointer and integral > types. > > > -- > Eric Botcazou >
