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Use on-demand ranges in ssa_name_has_boolean_range before querying nonzero bits.

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The function ssa_name_has_boolean_range looks at the nonzero bits stored
in SSA_NAME_RANGE_INFO.  These are global in nature and are the result
of a previous evrp/VRP run (technically other passes can also set them).

However, we can do better if we use get_range_query.  Doing so will use
a ranger if enabled in a pass, or global ranges otherwise.  The call to
get_nonzero_bits remains, as there are passes that will set them
independently of the global range info.

Tested on x86-64 Linux with a regstrap as well as in a DOM environment
using an on-demand ranger instead of evrp.

gcc/ChangeLog:

	* tree-ssanames.c (ssa_name_has_boolean_range): Use
	get_range_query.
This commit is contained in:
Aldy Hernandez 2021-09-27 09:20:56 +02:00
parent e1d01f4973
commit d5f8abe1d3
1 changed files with 14 additions and 5 deletions
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19
gcc/tree-ssanames.c
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@ -31,6 +31,7 @@ along with GCC; see the file COPYING3. If not see
#include "tree-ssa.h"
#include "cfgloop.h"
#include "tree-scalar-evolution.h"
#include "value-query.h"
/* Rewriting a function into SSA form can create a huge number of SSA_NAMEs,
many of which may be thrown away shortly after their creation if jumps
@ -484,7 +485,7 @@ get_nonzero_bits (const_tree name)
This can be because it is a boolean type, any unsigned integral
type with a single bit of precision, or has known range of [0..1]
via VRP analysis. */
via range analysis. */
bool
ssa_name_has_boolean_range (tree op)
@ -502,12 +503,20 @@ ssa_name_has_boolean_range (tree op)
return true;
/* An integral type with more precision, but the object
only takes on values [0..1] as determined by VRP
only takes on values [0..1] as determined by range
analysis. */
if (INTEGRAL_TYPE_P (TREE_TYPE (op))
&& (TYPE_PRECISION (TREE_TYPE (op)) > 1)
&& wi::eq_p (get_nonzero_bits (op), 1))
return true;
&& (TYPE_PRECISION (TREE_TYPE (op)) > 1))
{
int_range<2> onezero (build_zero_cst (TREE_TYPE (op)),
build_one_cst (TREE_TYPE (op)));
int_range<2> r;
if (get_range_query (cfun)->range_of_expr (r, op) && r == onezero)
return true;
if (wi::eq_p (get_nonzero_bits (op), 1))
return true;
}
return false;
}