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author | Andrew MacLeod <amacleod@redhat.com> | 2021-06-17 13:39:02 -0400 |
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committer | Andrew MacLeod <amacleod@redhat.com> | 2021-06-22 08:11:45 -0400 |
commit | 0f7ccc063a42407f91fa52a54cc480950a45e75c (patch) | |
tree | 9d0e5337cd18f98cb5fffde84d5f9675601f0be9 /gcc/range-op.cc | |
parent | ae6b830f31a47aca7ca24c4fea245c29214eef3a (diff) | |
download | gcc-0f7ccc063a42407f91fa52a54cc480950a45e75c.zip gcc-0f7ccc063a42407f91fa52a54cc480950a45e75c.tar.gz gcc-0f7ccc063a42407f91fa52a54cc480950a45e75c.tar.bz2 |
Add relation between LHS and op1 for casts and copies.
* range-op.cc (operator_cast::lhs_op1_relation): New.
(operator_identity::lhs_op1_relation): Mew.
Diffstat (limited to 'gcc/range-op.cc')
-rw-r--r-- | gcc/range-op.cc | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/gcc/range-op.cc b/gcc/range-op.cc index ec4816d..92b314d 100644 --- a/gcc/range-op.cc +++ b/gcc/range-op.cc @@ -2115,6 +2115,10 @@ public: const irange &lhs, const irange &op2, relation_kind rel = VREL_NONE) const; + virtual enum tree_code lhs_op1_relation (const irange &lhs, + const irange &op1, + const irange &op2) const; + private: bool truncating_cast_p (const irange &inner, const irange &outer) const; bool inside_domain_p (const wide_int &min, const wide_int &max, @@ -2123,6 +2127,27 @@ private: const irange &outer) const; } op_convert; +// Determine if there is a relationship between LHS and OP1. + +enum tree_code +operator_cast::lhs_op1_relation (const irange &lhs, + const irange &op1, + const irange &op2 ATTRIBUTE_UNUSED) const +{ + if (op1.undefined_p ()) + return VREL_NONE; + // We can't make larger types equivalent to smaller types because we can + // miss sign extensions in a chain of casts. + // u32 = 0xfffff + // s32 = (s32) u32 + // s64 = (s64) s32 + // we cant simply "convert" s64 = (s64)u32 or we get positive 0xffff + // value instead of sign extended negative value. + if (TYPE_PRECISION (lhs.type ()) == TYPE_PRECISION (op1.type ())) + return EQ_EXPR; + return VREL_NONE; +} + // Return TRUE if casting from INNER to OUTER is a truncating cast. inline bool @@ -3325,8 +3350,24 @@ public: const irange &lhs, const irange &op2, relation_kind rel = VREL_NONE) const; + virtual enum tree_code lhs_op1_relation (const irange &lhs, + const irange &op1, + const irange &op2) const; } op_identity; +// Determine if there is a relationship between LHS and OP1. + +enum tree_code +operator_identity::lhs_op1_relation (const irange &lhs, + const irange &op1 ATTRIBUTE_UNUSED, + const irange &op2 ATTRIBUTE_UNUSED) const +{ + if (lhs.undefined_p ()) + return VREL_NONE; + // Simply a copy, so they are equivalent. + return EQ_EXPR; +} + bool operator_identity::fold_range (irange &r, tree type ATTRIBUTE_UNUSED, const irange &lh, |