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-rw-r--r--gcc/ChangeLog7
-rw-r--r--gcc/combine.c9
2 files changed, 15 insertions, 1 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3e11726..ca7b3e8 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2013-11-30 Paulo Matos <pmatos@broadcom.com>
+ Eric Botcazou <ebotcazou@adacore.com>
+
+ * combine.c (reg_nonzero_bits_for_combine): Apply mask transformation
+ as applied to nonzero_sign_valid when last_set_mode has less precision
+ than mode.
+
2013-11-30 Tobias Burnus <burnus@net-b.de>
PR sanitizer/59275
diff --git a/gcc/combine.c b/gcc/combine.c
index d685a7f..25cf273 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -9472,7 +9472,13 @@ reg_nonzero_bits_for_combine (const_rtx x, enum machine_mode mode,
(DF_LR_IN (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb),
REGNO (x)))))
{
- *nonzero &= rsp->last_set_nonzero_bits;
+ unsigned HOST_WIDE_INT mask = rsp->last_set_nonzero_bits;
+
+ if (GET_MODE_PRECISION (rsp->last_set_mode) < GET_MODE_PRECISION (mode))
+ /* We don't know anything about the upper bits. */
+ mask |= GET_MODE_MASK (mode) ^ GET_MODE_MASK (rsp->last_set_mode);
+
+ *nonzero &= mask;
return NULL;
}
@@ -9505,6 +9511,7 @@ reg_nonzero_bits_for_combine (const_rtx x, enum machine_mode mode,
if (GET_MODE_PRECISION (GET_MODE (x)) < GET_MODE_PRECISION (mode))
/* We don't know anything about the upper bits. */
mask |= GET_MODE_MASK (mode) ^ GET_MODE_MASK (GET_MODE (x));
+
*nonzero &= mask;
}