diff options
| author | Xionghu Luo <luoxhu@linux.ibm.com> | 2020-05-10 21:06:20 -0500 |
|---|---|---|
| committer | Xionghu Luo <luoxhu@linux.ibm.com> | 2020-05-10 21:12:46 -0500 |
| commit | 0447929f11e6a3e1b076841712b90a8b6bc7d33a (patch) | |
| tree | ffc4b06c5fda9efeb839ecdea5cea6986b92169d /gcc/tree-affine.c | |
| parent | e7ae6d32c7df009973616d62829a431a6d206ccc (diff) | |
| download | gcc-0447929f11e6a3e1b076841712b90a8b6bc7d33a.zip gcc-0447929f11e6a3e1b076841712b90a8b6bc7d33a.tar.gz gcc-0447929f11e6a3e1b076841712b90a8b6bc7d33a.tar.bz2 | |
Add handling of MULT_EXPR/PLUS_EXPR for wrapping overflow in affine combination(PR83403)
Use determine_value_range to get value range info for fold convert expressions
with internal operation PLUS_EXPR/MINUS_EXPR/MULT_EXPR when not overflow on
wrapping overflow inner type. i.e.:
(long unsigned int)((unsigned int)n * 10 + 1)
=>
(long unsigned int)n * (long unsigned int)10 + (long unsigned int)1
With this patch for affine combination, load/store motion could detect
more address refs independency and promote some memory expressions to
registers within loop.
PS: Replace the previous "(T1)(X + CST) as (T1)X - (T1)(-CST))"
to "(T1)(X + CST) as (T1)X + (T1)(CST))" for wrapping overflow.
Bootstrap and regression tested pass on Power8-LE.
gcc/ChangeLog
2020-05-11 Xiong Hu Luo <luoxhu@linux.ibm.com>
PR tree-optimization/83403
* tree-affine.c (expr_to_aff_combination): Replace SSA_NAME with
determine_value_range, Add fold conversion of MULT_EXPR, fix the
previous PLUS_EXPR.
gcc/testsuite/ChangeLog
2020-05-11 Xiong Hu Luo <luoxhu@linux.ibm.com>
PR tree-optimization/83403
* gcc.dg/tree-ssa/pr83403-1.c: New test.
* gcc.dg/tree-ssa/pr83403-2.c: New test.
* gcc.dg/tree-ssa/pr83403.h: New header.
Diffstat (limited to 'gcc/tree-affine.c')
| -rw-r--r-- | gcc/tree-affine.c | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/gcc/tree-affine.c b/gcc/tree-affine.c index 0eb8db1..5620e6b 100644 --- a/gcc/tree-affine.c +++ b/gcc/tree-affine.c @@ -343,24 +343,28 @@ expr_to_aff_combination (aff_tree *comb, tree_code code, tree type, wide_int minv, maxv; /* If inner type has wrapping overflow behavior, fold conversion for below case: - (T1)(X - CST) -> (T1)X - (T1)CST - if X - CST doesn't overflow by range information. Also handle - (T1)(X + CST) as (T1)(X - (-CST)). */ + (T1)(X *+- CST) -> (T1)X *+- (T1)CST + if X *+- CST doesn't overflow by range information. */ if (TYPE_UNSIGNED (itype) && TYPE_OVERFLOW_WRAPS (itype) - && TREE_CODE (op0) == SSA_NAME && TREE_CODE (op1) == INTEGER_CST - && icode != MULT_EXPR - && get_range_info (op0, &minv, &maxv) == VR_RANGE) + && determine_value_range (op0, &minv, &maxv) == VR_RANGE) { + wi::overflow_type overflow = wi::OVF_NONE; + signop sign = UNSIGNED; if (icode == PLUS_EXPR) - op1 = wide_int_to_tree (itype, -wi::to_wide (op1)); - if (wi::geu_p (minv, wi::to_wide (op1))) + wi::add (maxv, wi::to_wide (op1), sign, &overflow); + else if (icode == MULT_EXPR) + wi::mul (maxv, wi::to_wide (op1), sign, &overflow); + else + wi::sub (minv, wi::to_wide (op1), sign, &overflow); + + if (overflow == wi::OVF_NONE) { op0 = fold_convert (otype, op0); op1 = fold_convert (otype, op1); - return expr_to_aff_combination (comb, MINUS_EXPR, otype, - op0, op1); + return expr_to_aff_combination (comb, icode, otype, op0, + op1); } } } |