| Message ID | 20241111115545.31217-1-quic_eikagupt@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] MATCH: Simplify `min(a, b) op max(a, b)` to `a op b` [PR109401] | expand |
On 11/11/24 4:55 AM, Eikansh Gupta wrote: > This patch simplify `min(a,b) op max(a,b)` to `a op b`. This optimization > will work for all the binary commutative operations. So, the `op` here can > be one of {plus, mult, bit_and, bit_xor, bit_ior, eq, ne, min, max}. > > PR tree-optimization/109878 > PR 109401 > > gcc/ChangeLog: > > * match.pd (min(a,b) op max(a,b) -> a op b): New pattern. > > gcc/testsuite/ChangeLog: > > * gcc.dg/tree-ssa/pr109401.c: New test. > * gcc.dg/tree-ssa/pr109401-1.c: New test. It seems to me this ought to work when the min/max reversed as well, or am I missing something? jeff
Hi, > It seems to me this ought to work when the min/max reversed as well, or > am I missing something? Yes, it should work when min/max are reversed. Regards, Eikansh
On 11/11/24 9:32 PM, Eikansh Gupta wrote: > Hi, > > > It seems to me this ought to work when the min/max reversed > as well, or > > am I missing something? > > Yes, it should work when min/max are reversed. So are you going to add support for both? Seems to me like we'd want to support both orders. jeff
On Thu, Nov 14, 2024 at 5:30 PM Jeff Law <jeffreyalaw@gmail.com> wrote: > > > > On 11/11/24 9:32 PM, Eikansh Gupta wrote: > > Hi, > > > > > It seems to me this ought to work when the min/max reversed > > as well, or > > > am I missing something? > > > > Yes, it should work when min/max are reversed. > So are you going to add support for both? Seems to me like we'd want to > support both orders. Both orders are already supported: + (op:c (min:c @0 @1) (max @0 @1)) Notice the `:c` on op. It means both `(plus (min @0 @1) (max @0 @1) )` and `(plus (max @0 @1) (min @0 @1) )` will match. Unless I am misunderstanding something here too. Thanks, Andrew Pinski > > jeff >
Hi Jeff, The patch has support for both. In the test cases, approx half the test cases have min(a, b) op max(a, b) and the other half have max(a, b) op min(a, b). Regards, Eikansh
On 11/15/24 5:16 AM, Eikansh Gupta wrote: > Hi Jeff, > > The patch has support for both. In the test cases, approx half the test > cases have |min(a, b) op max(a, b)| and the other half have |max(a, b) > op min(a, b). | For some reason my brain just doesn't parse match.pd code well. OK for the trunk. jeff
On Sat, Nov 16, 2024 at 10:48 AM Jeff Law <jeffreyalaw@gmail.com> wrote: > > > > > On 11/15/24 5:16 AM, Eikansh Gupta wrote: > > Hi Jeff, > > > > The patch has support for both. In the test cases, approx half the test > > cases have |min(a, b) op max(a, b)| and the other half have |max(a, b) > > op min(a, b). | > For some reason my brain just doesn't parse match.pd code well. > > OK for the trunk. Pushed as r15-5355 with small changes to the commit message dealing with the format in the changelog. Thanks, Andrew > > jeff >
diff --git a/gcc/match.pd b/gcc/match.pd index 00988241348..bbc7d708f32 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -4660,6 +4660,13 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) @0 @2))) +/* min (a, b) op max (a, b) -> a op b */ +(for op (plus mult bit_and bit_xor bit_ior eq ne min max) + (simplify + (op:c (min:c @0 @1) (max @0 @1)) + (if (!HONOR_NANS (@0)) + (op @0 @1)))) + /* Simplify min (&var[off0], &var[off1]) etc. depending on whether the addresses are known to be less, equal or greater. */ (for minmax (min max) diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr109401-1.c b/gcc/testsuite/gcc.dg/tree-ssa/pr109401-1.c new file mode 100644 index 00000000000..3f72516c293 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr109401-1.c @@ -0,0 +1,35 @@ +/* PR tree-optimization/109878 */ +/* { dg-do compile } */ +/* { dg-options "-O1 -fdump-tree-optimized" } */ + +/* Returns max (a, b) */ +int max(int a, int b) { + if (b > a) + return b; + else + return a; +} + +/* Returns min (a, b) */ +int min(int a, int b) { + if (b < a) + return b; + else + return a; +} + +/* These functions should return a op b */ +int f8(int a, int b) +{ + return min (max (a, b), min (a, b)); +} + +int f9(int a, int b) +{ + return max (min (a, b), max (a, b)); +} + +/* Function min and f8 should have MIN_EXPR */ +/* Function max and f9 should have MAX_EXPR */ +/* { dg-final { scan-tree-dump-times "MIN_EXPR" 2 "optimized" } } */ +/* { dg-final { scan-tree-dump-times "MAX_EXPR" 2 "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr109401.c b/gcc/testsuite/gcc.dg/tree-ssa/pr109401.c new file mode 100644 index 00000000000..11177d97fbf --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr109401.c @@ -0,0 +1,61 @@ +/* PR tree-optimization/109878 */ +/* { dg-do compile } */ +/* { dg-options "-O1 -fdump-tree-optimized" } */ + +/* Returns max (a, b) */ +int max(int a, int b) { + if (b > a) + return b; + else + return a; +} + +/* Returns min (a, b) */ +int min(int a, int b) { + if (b < a) + return b; + else + return a; +} + +/* All the functions here shouldn't evalute min or max of a and b + * These functions should return a op b */ +int f(int a, int b) +{ + return max (a, b) + min (a, b); +} + +int f1(int a, int b) +{ + return max (a, b) * min (a, b); +} + +int f2(int a, int b) +{ + return max (a, b) | min (a, b); +} + +int f3(int a, int b) +{ + return max (a, b) & min (a, b); +} + +int f5(int a, int b) +{ + return min (a, b) ^ max (a, b); +} + +int f6(int a, int b) +{ + return min (a, b) == max (a, b); +} + +int f7(int a, int b) +{ + return min (a, b) != max (a, b); +} + +/* Function min should have MIN_EXPR */ +/* Function max should have MAX_EXPR */ +/* { dg-final { scan-tree-dump-times "MIN_EXPR" 1 "optimized" } } */ +/* { dg-final { scan-tree-dump-times "MAX_EXPR" 1 "optimized" } } */
This patch simplify `min(a,b) op max(a,b)` to `a op b`. This optimization will work for all the binary commutative operations. So, the `op` here can be one of {plus, mult, bit_and, bit_xor, bit_ior, eq, ne, min, max}. PR tree-optimization/109878 PR 109401 gcc/ChangeLog: * match.pd (min(a,b) op max(a,b) -> a op b): New pattern. gcc/testsuite/ChangeLog: * gcc.dg/tree-ssa/pr109401.c: New test. * gcc.dg/tree-ssa/pr109401-1.c: New test. Signed-off-by: Eikansh Gupta <quic_eikagupt@quicinc.com> --- gcc/match.pd | 7 +++ gcc/testsuite/gcc.dg/tree-ssa/pr109401-1.c | 35 +++++++++++++ gcc/testsuite/gcc.dg/tree-ssa/pr109401.c | 61 ++++++++++++++++++++++ 3 files changed, 103 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr109401-1.c create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr109401.c