From 06bedc3860d3e61857d72ffe699f79ed5c92855f Mon Sep 17 00:00:00 2001 From: Andrew Pinski Date: Tue, 12 Sep 2023 05:16:06 +0000 Subject: [PATCH] MATCH: [PR111364] Add some more minmax cmp operand simplifications This adds a few more minmax cmp operand simplifications which were missed before. `MIN(a,b) < a` -> `a > b` `MIN(a,b) >= a` -> `a <= b` `MAX(a,b) > a` -> `a < b` `MAX(a,b) <= a` -> `a >= b` OK? Bootstrapped and tested on x86_64-linux-gnu. Note gcc.dg/pr96708-negative.c needed to updated to remove the check for MIN/MAX as they have been optimized (correctly) away. PR tree-optimization/111364 gcc/ChangeLog: * match.pd (`MIN (X, Y) == X`): Extend to min/lt, min/ge, max/gt, max/le. gcc/testsuite/ChangeLog: * gcc.c-torture/execute/minmaxcmp-1.c: New test. * gcc.dg/tree-ssa/minmaxcmp-2.c: New test. * gcc.dg/pr96708-negative.c: Update testcase. * gcc.dg/pr96708-positive.c: Add comment about `return 0`. --- gcc/match.pd | 8 +-- .../gcc.c-torture/execute/minmaxcmp-1.c | 51 +++++++++++++++++++ gcc/testsuite/gcc.dg/pr96708-negative.c | 4 +- gcc/testsuite/gcc.dg/pr96708-positive.c | 1 + gcc/testsuite/gcc.dg/tree-ssa/minmaxcmp-2.c | 30 +++++++++++ 5 files changed, 89 insertions(+), 5 deletions(-) create mode 100644 gcc/testsuite/gcc.c-torture/execute/minmaxcmp-1.c create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/minmaxcmp-2.c diff --git a/gcc/match.pd b/gcc/match.pd index 0d865d8295f..ea4c7c5cf53 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -3918,9 +3918,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (maxmin @0 (bit_not @1)))) /* MIN (X, Y) == X -> X <= Y */ -(for minmax (min min max max) - cmp (eq ne eq ne ) - out (le gt ge lt ) +/* MIN (X, Y) < X -> X > Y */ +/* MIN (X, Y) >= X -> X <= Y */ +(for minmax (min min min min max max max max) + cmp (eq ne lt ge eq ne gt le ) + out (le gt gt le ge lt lt ge ) (simplify (cmp:c (minmax:c @0 @1) @0) (if (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))) diff --git a/gcc/testsuite/gcc.c-torture/execute/minmaxcmp-1.c b/gcc/testsuite/gcc.c-torture/execute/minmaxcmp-1.c new file mode 100644 index 00000000000..6705a053768 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/minmaxcmp-1.c @@ -0,0 +1,51 @@ +#define func(vol, op1, op2) \ +_Bool op1##_##op2##_##vol (int a, int b) \ +{ \ + vol int x = op_##op1(a, b); \ + return op_##op2(x, a); \ +} + +#define op_lt(a, b) ((a) < (b)) +#define op_le(a, b) ((a) <= (b)) +#define op_eq(a, b) ((a) == (b)) +#define op_ne(a, b) ((a) != (b)) +#define op_gt(a, b) ((a) > (b)) +#define op_ge(a, b) ((a) >= (b)) +#define op_min(a, b) ((a) < (b) ? (a) : (b)) +#define op_max(a, b) ((a) > (b) ? (a) : (b)) + + +#define funcs(a) \ + a(min,lt) \ + a(max,lt) \ + a(min,gt) \ + a(max,gt) \ + a(min,le) \ + a(max,le) \ + a(min,ge) \ + a(max,ge) \ + a(min,ne) \ + a(max,ne) \ + a(min,eq) \ + a(max,eq) + +#define funcs1(a,b) \ +func(,a,b) \ +func(volatile,a,b) + +funcs(funcs1) + +#define test(op1,op2) \ +do { \ + if (op1##_##op2##_(x,y) != op1##_##op2##_volatile(x,y)) \ + __builtin_abort(); \ +} while(0); + +int main() +{ + for(int x = -10; x < 10; x++) + for(int y = -10; y < 10; y++) + { + funcs(test) + } +} diff --git a/gcc/testsuite/gcc.dg/pr96708-negative.c b/gcc/testsuite/gcc.dg/pr96708-negative.c index 91964d3b971..c9c1aa85558 100644 --- a/gcc/testsuite/gcc.dg/pr96708-negative.c +++ b/gcc/testsuite/gcc.dg/pr96708-negative.c @@ -42,7 +42,7 @@ int main() return 0; } -/* { dg-final { scan-tree-dump-times "MAX_EXPR" 2 "optimized" } } */ -/* { dg-final { scan-tree-dump-times "MIN_EXPR" 2 "optimized" } } */ +/* Even though test[1-4] originally has MIN/MAX, those can be optimized away + into just comparing a and b arguments. */ /* { dg-final { scan-tree-dump-times "return 0;" 1 "optimized" } } */ /* { dg-final { scan-tree-dump-not { "return 1;" } "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/pr96708-positive.c b/gcc/testsuite/gcc.dg/pr96708-positive.c index 65af85344b6..12c5fedfd30 100644 --- a/gcc/testsuite/gcc.dg/pr96708-positive.c +++ b/gcc/testsuite/gcc.dg/pr96708-positive.c @@ -42,6 +42,7 @@ int main() return 0; } +/* Note main has one `return 0`. */ /* { dg-final { scan-tree-dump-times "return 0;" 3 "optimized" } } */ /* { dg-final { scan-tree-dump-times "return 1;" 2 "optimized" } } */ /* { dg-final { scan-tree-dump-not { "MAX_EXPR" } "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmaxcmp-2.c b/gcc/testsuite/gcc.dg/tree-ssa/minmaxcmp-2.c new file mode 100644 index 00000000000..f64a9253cfb --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/minmaxcmp-2.c @@ -0,0 +1,30 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-original" } */ +/* PR tree-optimization/111364 */ + +#define min1(a, b) ((a) < (b) ? (a) : (b)) +#define max1(a, b) ((a) > (b) ? (a) : (b)) + +int minlt(int a, int b) +{ + return min1(a, b) < a; // b < a or a > b +} +/* { dg-final { scan-tree-dump "return a > b;|return b < a;" "original" } } */ + +int minge(int c, int d) +{ + return min1(c, d) >= c; // d >= c or c <= d +} +/* { dg-final { scan-tree-dump "return c <= d;|return d <= c;" "original" } } */ + +int maxgt(int e, int f) +{ + return max1(e, f) > e; // e > f or f < e +} +/* { dg-final { scan-tree-dump "return e < f;|return f > e;" "original" } } */ + +int maxle(int x, int y) +{ + return max1(x, y) <= x; // y <= x or x >= y +} +/* { dg-final { scan-tree-dump "return x >= y;|return y <= x;" "original" } } */