Hi!
The following patch is an incremental change to the PR30314 enhancement,
this one handles signed types.
For signed types (but still, the same for 1st and result element type
and non-zero constant that fits into that type), we actually need to
watch for overflow in direction to positive and negative infinity
and it also depends on whether the cst operand is positive or negative.
For __builtin_mul_overflow_p (x, cst, (stype) 0):
For cst > 0, we can simplify it to:
x > INT_MAX / cst || x < INT_MIN / cst
aka:
x + (unsigned) (INT_MIN / cst) > (unsigned) (INT_MAX / cst) - (unsigned)
(INT_MIN / cst)
and for cst < 0 to:
x < INT_MAX / cst || x > INT_MIN / cst
aka:
x + (unsigned) (INT_MAX / cst) > (unsigned) (INT_MIN / cst) - (unsigned)
(INT_MAX / cst)
Additionally, I've added executable testcases, so we don't just check for
the optimization to be performed, but also that it is correct (done that
even for the other PR's testcase).
Starting x86_64-linux and i686-linux bootstrap/regtest, ok for trunk if
it passes them?
2022-06-02 Jakub Jelinek <ja...@redhat.com>
PR middle-end/30314
PR middle-end/105777
* match.pd (__builtin_mul_overflow_p (x, cst, (stype) 0) ->
x > stype_max / cst || x < stype_min / cst): New simplification.
* gcc.dg/tree-ssa/pr30314.c: Add noipa attribute to all functions.
* gcc.dg/tree-ssa/pr105777.c: New test.
* gcc.c-torture/execute/pr30314.c: New test.
* gcc.c-torture/execute/pr105777.c: New test.
--- gcc/match.pd.jj 2022-06-01 17:54:30.536372912 +0200
+++ gcc/match.pd 2022-06-02 13:16:17.171415948 +0200
@@ -5970,15 +5970,37 @@ (define_operator_list SYNC_FETCH_AND_AND
(ovf @1 @0))))
/* Optimize __builtin_mul_overflow_p (x, cst, (utype) 0) if all 3 types
- are unsigned to x > (umax / cst). */
+ are unsigned to x > (umax / cst). Similarly for signed type, but
+ in that case it needs to be outside of a range. */
(simplify
(imagpart (IFN_MUL_OVERFLOW:cs@2 @0 integer_nonzerop@1))
(if (INTEGRAL_TYPE_P (TREE_TYPE (@0))
- && TYPE_UNSIGNED (TREE_TYPE (@0))
&& TYPE_MAX_VALUE (TREE_TYPE (@0))
&& types_match (TREE_TYPE (@0), TREE_TYPE (TREE_TYPE (@2)))
&& int_fits_type_p (@1, TREE_TYPE (@0)))
- (convert (gt @0 (trunc_div! { TYPE_MAX_VALUE (TREE_TYPE (@0)); } @1)))))
+ (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
+ (convert (gt @0 (trunc_div! { TYPE_MAX_VALUE (TREE_TYPE (@0)); } @1)))
+ (if (TYPE_MIN_VALUE (TREE_TYPE (@0)))
+ (with
+ {
+ tree lo = int_const_binop (TRUNC_DIV_EXPR,
+ TYPE_MIN_VALUE (TREE_TYPE (@0)),
+ fold_convert (TREE_TYPE (@0), @1));
+ tree hi = int_const_binop (TRUNC_DIV_EXPR,
+ TYPE_MAX_VALUE (TREE_TYPE (@0)),
+ fold_convert (TREE_TYPE (@0), @1));
+ tree etype = range_check_type (TREE_TYPE (@0));
+ if (etype)
+ {
+ if (wi::neg_p (wi::to_wide (@1)))
+ std::swap (lo, hi);
+ lo = fold_convert (etype, lo);
+ hi = fold_convert (etype, hi);
+ hi = int_const_binop (MINUS_EXPR, hi, lo);
+ }
+ }
+ (if (etype)
+ (convert (gt (minus (convert:etype @0) { lo; }) { hi; }))))))))
/* Simplification of math builtins. These rules must all be optimizations
as well as IL simplifications. If there is a possibility that the new
--- gcc/testsuite/gcc.dg/tree-ssa/pr30314.c.jj 2022-06-02 11:17:23.689835550
+0200
+++ gcc/testsuite/gcc.dg/tree-ssa/pr30314.c 2022-06-02 14:23:19.294093445
+0200
@@ -7,25 +7,25 @@
/* { dg-final { scan-tree-dump " > 102261126" "optimized" { target int32 } } }
*/
/* { dg-final { scan-tree-dump " > 439208192231179800" "optimized" { target
lp64 } } } */
-int
+__attribute__((noipa)) int
foo (unsigned int x)
{
return __builtin_mul_overflow_p (x, 35U, 0U);
}
-int
+__attribute__((noipa)) int
bar (unsigned long int x)
{
return __builtin_mul_overflow_p (x, 35UL, 0UL);
}
-int
+__attribute__((noipa)) int
baz (unsigned int x)
{
return __builtin_mul_overflow_p (42, x, 0U);
}
-int
+__attribute__((noipa)) int
qux (unsigned long int x)
{
return __builtin_mul_overflow_p (42, x, 0UL);
--- gcc/testsuite/gcc.dg/tree-ssa/pr105777.c.jj 2022-06-02 14:22:57.017328731
+0200
+++ gcc/testsuite/gcc.dg/tree-ssa/pr105777.c 2022-06-02 14:19:29.399521503
+0200
@@ -0,0 +1,68 @@
+/* PR middle-end/105777 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+/* { dg-final { scan-tree-dump-not "\.MUL_OVERFLOW " "optimized" } } */
+/* { dg-final { scan-tree-dump " \\+ 61356675;" "optimized" { target int32 } }
} */
+/* { dg-final { scan-tree-dump " > 122713350" "optimized" { target int32 } } }
*/
+/* { dg-final { scan-tree-dump " \\+ 263524915338707880" "optimized" { target
lp64 } } } */
+/* { dg-final { scan-tree-dump " > 527049830677415760" "optimized" { target
lp64 } } } */
+/* { dg-final { scan-tree-dump " \\+ 51130563" "optimized" { target int32 } }
} */
+/* { dg-final { scan-tree-dump " > 102261126" "optimized" { target int32 } } }
*/
+/* { dg-final { scan-tree-dump " \\+ 219604096115589900" "optimized" { target
lp64 } } } */
+/* { dg-final { scan-tree-dump " > 439208192231179800" "optimized" { target
lp64 } } } */
+/* { dg-final { scan-tree-dump " \\+ 55063683;" "optimized" { target int32 } }
} */
+/* { dg-final { scan-tree-dump " > 110127366" "optimized" { target int32 } } }
*/
+/* { dg-final { scan-tree-dump " \\+ 236496718893712200" "optimized" { target
lp64 } } } */
+/* { dg-final { scan-tree-dump " > 472993437787424400" "optimized" { target
lp64 } } } */
+/* { dg-final { scan-tree-dump " \\+ 46684427" "optimized" { target int32 } }
} */
+/* { dg-final { scan-tree-dump " > 93368854" "optimized" { target int32 } } }
*/
+/* { dg-final { scan-tree-dump " \\+ 200508087757712517" "optimized" { target
lp64 } } } */
+/* { dg-final { scan-tree-dump " > 401016175515425034" "optimized" { target
lp64 } } } */
+
+__attribute__((noipa)) int
+foo (int x)
+{
+ return __builtin_mul_overflow_p (x, 35, 0);
+}
+
+__attribute__((noipa)) int
+bar (long int x)
+{
+ return __builtin_mul_overflow_p (x, 35L, 0L);
+}
+
+__attribute__((noipa)) int
+baz (int x)
+{
+ return __builtin_mul_overflow_p (42, x, 0);
+}
+
+__attribute__((noipa)) int
+qux (long int x)
+{
+ return __builtin_mul_overflow_p (42, x, 0L);
+}
+
+__attribute__((noipa)) int
+corge (int x)
+{
+ return __builtin_mul_overflow_p (x, -39, 0);
+}
+
+__attribute__((noipa)) int
+garply (long int x)
+{
+ return __builtin_mul_overflow_p (x, -39L, 0L);
+}
+
+__attribute__((noipa)) int
+grault (int x)
+{
+ return __builtin_mul_overflow_p (-46, x, 0);
+}
+
+__attribute__((noipa)) int
+waldo (long int x)
+{
+ return __builtin_mul_overflow_p (-46, x, 0L);
+}
--- gcc/testsuite/gcc.c-torture/execute/pr30314.c.jj 2022-06-02
14:32:30.070276332 +0200
+++ gcc/testsuite/gcc.c-torture/execute/pr30314.c 2022-06-02
14:32:22.121360286 +0200
@@ -0,0 +1,29 @@
+/* PR middle-end/30314 */
+
+#include "../../gcc.dg/tree-ssa/pr30314.c"
+
+int
+main ()
+{
+ if (foo (0) != 0
+ || foo (~0U / 35) != 0
+ || foo (~0U / 35 + 1) != 1
+ || foo (~0U) != 1)
+ __builtin_abort ();
+ if (bar (0) != 0
+ || bar (~0UL / 35) != 0
+ || bar (~0UL / 35 + 1) != 1
+ || bar (~0UL) != 1)
+ __builtin_abort ();
+ if (baz (0) != 0
+ || baz (~0U / 42) != 0
+ || baz (~0U / 42 + 1) != 1
+ || baz (~0U) != 1)
+ __builtin_abort ();
+ if (qux (0) != 0
+ || qux (~0UL / 42) != 0
+ || qux (~0UL / 42 + 1) != 1
+ || qux (~0UL) != 1)
+ __builtin_abort ();
+ return 0;
+}
--- gcc/testsuite/gcc.c-torture/execute/pr105777.c.jj 2022-06-02
14:32:50.287062810 +0200
+++ gcc/testsuite/gcc.c-torture/execute/pr105777.c 2022-06-02
14:38:36.289409212 +0200
@@ -0,0 +1,73 @@
+/* PR middle-end/105777 */
+
+#include "../../gcc.dg/tree-ssa/pr105777.c"
+
+int
+main ()
+{
+ if (foo (0) != 0
+ || foo (__INT_MAX__ / 35) != 0
+ || foo (__INT_MAX__ / 35 + 1) != 1
+ || foo (__INT_MAX__) != 1
+ || foo ((-__INT_MAX__ - 1) / 35) != 0
+ || foo ((-__INT_MAX__ - 1) / 35 - 1) != 1
+ || foo (-__INT_MAX__ - 1) != 1)
+ __builtin_abort ();
+ if (bar (0) != 0
+ || bar (__LONG_MAX__ / 35) != 0
+ || bar (__LONG_MAX__ / 35 + 1) != 1
+ || bar (__LONG_MAX__) != 1
+ || bar ((-__LONG_MAX__ - 1) / 35) != 0
+ || bar ((-__LONG_MAX__ - 1) / 35 - 1) != 1
+ || bar (-__LONG_MAX__ - 1) != 1)
+ __builtin_abort ();
+ if (baz (0) != 0
+ || baz (__INT_MAX__ / 42) != 0
+ || baz (__INT_MAX__ / 42 + 1) != 1
+ || baz (__INT_MAX__) != 1
+ || baz ((-__INT_MAX__ - 1) / 42) != 0
+ || baz ((-__INT_MAX__ - 1) / 42 - 1) != 1
+ || baz (-__INT_MAX__ - 1) != 1)
+ __builtin_abort ();
+ if (qux (0) != 0
+ || qux (__LONG_MAX__ / 42) != 0
+ || qux (__LONG_MAX__ / 42 + 1) != 1
+ || qux (__LONG_MAX__) != 1
+ || qux ((-__LONG_MAX__ - 1) / 42) != 0
+ || qux ((-__LONG_MAX__ - 1) / 42 - 1) != 1
+ || qux (-__LONG_MAX__ - 1) != 1)
+ __builtin_abort ();
+ if (corge (0) != 0
+ || corge (__INT_MAX__ / -39) != 0
+ || corge (__INT_MAX__ / -39 - 1) != 1
+ || corge (__INT_MAX__) != 1
+ || corge ((-__INT_MAX__ - 1) / -39) != 0
+ || corge ((-__INT_MAX__ - 1) / -39 + 1) != 1
+ || corge (-__INT_MAX__ - 1) != 1)
+ __builtin_abort ();
+ if (garply (0) != 0
+ || garply (__LONG_MAX__ / -39) != 0
+ || garply (__LONG_MAX__ / -39 - 1) != 1
+ || garply (__LONG_MAX__) != 1
+ || garply ((-__LONG_MAX__ - 1) / -39) != 0
+ || garply ((-__LONG_MAX__ - 1) / -39 + 1) != 1
+ || garply (-__LONG_MAX__ - 1) != 1)
+ __builtin_abort ();
+ if (grault (0) != 0
+ || grault (__INT_MAX__ / -46) != 0
+ || grault (__INT_MAX__ / -46 - 1) != 1
+ || grault (__INT_MAX__) != 1
+ || grault ((-__INT_MAX__ - 1) / -46) != 0
+ || grault ((-__INT_MAX__ - 1) / -46 + 1) != 1
+ || grault (-__INT_MAX__ - 1) != 1)
+ __builtin_abort ();
+ if (waldo (0) != 0
+ || waldo (__LONG_MAX__ / -46) != 0
+ || waldo (__LONG_MAX__ / -46 - 1) != 1
+ || waldo (__LONG_MAX__) != 1
+ || waldo ((-__LONG_MAX__ - 1) / -46) != 0
+ || waldo ((-__LONG_MAX__ - 1) / -46 + 1) != 1
+ || waldo (-__LONG_MAX__ - 1) != 1)
+ __builtin_abort ();
+ return 0;
+}
Jakub
