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authorRobert Suchanek <robert.suchanek@imgtec.com>2015-01-16 12:31:01 +0000
committerMatthew Fortune <mpf@gcc.gnu.org>2015-01-16 12:31:01 +0000
commitece4d1aca6232a26f44e8fa5435f429f9bcde6db (patch)
tree24118a1005abdf80d65240f679378bcda19c1867 /gcc/simplify-rtx.c
parent4baa25d3fbee279835c1e7e53ef1460d41291b28 (diff)
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Account for high/lo_sum simplification with displacements
gcc/ * simplify-rtx.c (simplify_replace_fn_rtx): Simplify (lo_sum (high x) y) to y if x and y have the same base. gcc/testsuite/ * gcc.c-torture/compile/20150108.c: New test. From-SVN: r219729
Diffstat (limited to 'gcc/simplify-rtx.c')
-rw-r--r--gcc/simplify-rtx.c12
1 files changed, 9 insertions, 3 deletions
diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index 4ee63d2..d26267d 100644
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -539,9 +539,15 @@ simplify_replace_fn_rtx (rtx x, const_rtx old_rtx,
op0 = simplify_replace_fn_rtx (XEXP (x, 0), old_rtx, fn, data);
op1 = simplify_replace_fn_rtx (XEXP (x, 1), old_rtx, fn, data);
- /* (lo_sum (high x) x) -> x */
- if (GET_CODE (op0) == HIGH && rtx_equal_p (XEXP (op0, 0), op1))
- return op1;
+ /* (lo_sum (high x) y) -> y where x and y have the same base. */
+ if (GET_CODE (op0) == HIGH)
+ {
+ rtx base0, base1, offset0, offset1;
+ split_const (XEXP (op0, 0), &base0, &offset0);
+ split_const (op1, &base1, &offset1);
+ if (rtx_equal_p (base0, base1))
+ return op1;
+ }
if (op0 == XEXP (x, 0) && op1 == XEXP (x, 1))
return x;