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Make get_value_for_expr check for INTEGER_CSTs
- From: Richard Sandiford <richard dot sandiford at arm dot com>
- To: gcc-patches at gcc dot gnu dot org
- Date: Wed, 18 Sep 2019 07:54:34 +0100
- Subject: Make get_value_for_expr check for INTEGER_CSTs
CONSTANT lattice values are symbolic constants rather than
compile-time constants, so among other things can be POLY_INT_CSTs.
This patch fixes a case in which we assumed all CONSTANTs were either
ADDR_EXPRs or INTEGER_CSTs.
This is tested by later SVE patches.
Tested on aarch64-linux-gnu with SVE (with and without follow-on
patches) and x86_64-linux-gnu. OK to install?
Richard
2019-09-18 Richard Sandiford <richard.sandiford@arm.com>
gcc/
* tree-ssa-ccp.c (get_value_for_expr): Check whether CONSTANTs
are INTEGER_CSTs.
Index: gcc/tree-ssa-ccp.c
===================================================================
--- gcc/tree-ssa-ccp.c 2019-08-21 14:58:05.999057076 +0100
+++ gcc/tree-ssa-ccp.c 2019-09-18 07:53:36.930481545 +0100
@@ -615,9 +615,17 @@ get_value_for_expr (tree expr, bool for_
val.mask = -1;
}
if (for_bits_p
- && val.lattice_val == CONSTANT
- && TREE_CODE (val.value) == ADDR_EXPR)
- val = get_value_from_alignment (val.value);
+ && val.lattice_val == CONSTANT)
+ {
+ if (TREE_CODE (val.value) == ADDR_EXPR)
+ val = get_value_from_alignment (val.value);
+ else if (TREE_CODE (val.value) != INTEGER_CST)
+ {
+ val.lattice_val = VARYING;
+ val.value = NULL_TREE;
+ val.mask = -1;
+ }
+ }
/* Fall back to a copy value. */
if (!for_bits_p
&& val.lattice_val == VARYING