tree-ssa-coalesce.h File Reference

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Functions
var_map	coalesce_ssa_name (void)

---

Function Documentation

var_map coalesce_ssa_name

(

void

)

Header file for tree-ssa-coalesce.c exports. Copyright (C) 2013 Free Software Foundation, Inc.

This file is part of GCC.

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Reduce the number of copies by coalescing variables in the function. Return a partition map with the resulting coalesces.

 We need to coalesce all names originating same SSA_NAME_VAR
 so debug info remains undisturbed.   

 Don't calculate live ranges for variables not in the coalesce list.   

 Build a conflict graph.   

 First, coalesce all live on entry variables to their base variable.
 This will ensure the first use is coming from the correct location.   

 Now coalesce everything in the list.