This patch adds the following match patterns to optimize these: /* (a != b) ? (a - b) : 0 -> (a - b) */ /* (a != b) ? (a ^ b) : 0 -> (a ^ b) */ /* (a != b) ? (a & b) : a -> (a & b) */ /* (a != b) ? (a | b) : a -> (a | b) */ /* (a != b) ? min(a,b) : a -> min(a,b) */ /* (a != b) ? max(a,b) : a -> max(a,b) */ /* (a != b) ? (a * b) : (a * a) -> (a * b) */ /* (a != b) ? (a + b) : (a + a) -> (a + b) */ /* (a != b) ? (a + b) : (2 * a) -> (a + b) */ Note currently only integer types (include vector types) are handled. Floating point types can be added later on.
OK? Bootstrapped and tested on x86_64-linux-gnu. The first pattern had still shows up in GCC in cse.c's preferable function which was the original motivation for this patch. PR tree-optimization/19832 gcc/ChangeLog: * match.pd: Add pattern to optimize `(a != b) ? a OP b : c`. gcc/testsuite/ChangeLog: * g++.dg/opt/vectcond-1.C: New test. * gcc.dg/tree-ssa/phi-opt-same-1.c: New test. --- gcc/match.pd | 31 ++++++++++ gcc/testsuite/g++.dg/opt/vectcond-1.C | 57 ++++++++++++++++++ .../gcc.dg/tree-ssa/phi-opt-same-1.c | 60 +++++++++++++++++++ 3 files changed, 148 insertions(+) create mode 100644 gcc/testsuite/g++.dg/opt/vectcond-1.C create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/phi-opt-same-1.c diff --git a/gcc/match.pd b/gcc/match.pd index c01362ee359..487a7e38719 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -5261,6 +5261,37 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (convert @c0)))))))) #endif +(for cnd (cond vec_cond) + /* (a != b) ? (a - b) : 0 -> (a - b) */ + (simplify + (cnd (ne:c @0 @1) (minus@2 @0 @1) integer_zerop) + @2) + /* (a != b) ? (a ^ b) : 0 -> (a ^ b) */ + (simplify + (cnd (ne:c @0 @1) (bit_xor:c@2 @0 @1) integer_zerop) + @2) + /* (a != b) ? (a & b) : a -> (a & b) */ + /* (a != b) ? (a | b) : a -> (a | b) */ + /* (a != b) ? min(a,b) : a -> min(a,b) */ + /* (a != b) ? max(a,b) : a -> max(a,b) */ + (for op (bit_and bit_ior min max) + (simplify + (cnd (ne:c @0 @1) (op:c@2 @0 @1) @0) + @2)) + /* (a != b) ? (a * b) : (a * a) -> (a * b) */ + /* (a != b) ? (a + b) : (a + a) -> (a + b) */ + (for op (mult plus) + (simplify + (cnd (ne:c @0 @1) (op@2 @0 @1) (op @0 @0)) + (if (ANY_INTEGRAL_TYPE_P (type)) + @2))) + /* (a != b) ? (a + b) : (2 * a) -> (a + b) */ + (simplify + (cnd (ne:c @0 @1) (plus@2 @0 @1) (mult @0 uniform_integer_cst_p@3)) + (if (wi::to_wide (uniform_integer_cst_p (@3)) == 2) + @2)) +) + /* These was part of minmax phiopt. */ /* Optimize (a CMP b) ? minmax<a, c> : minmax<b, c> to minmax<min/max<a, b>, c> */ diff --git a/gcc/testsuite/g++.dg/opt/vectcond-1.C b/gcc/testsuite/g++.dg/opt/vectcond-1.C new file mode 100644 index 00000000000..3877ad11414 --- /dev/null +++ b/gcc/testsuite/g++.dg/opt/vectcond-1.C @@ -0,0 +1,57 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-ccp1 -fdump-tree-optimized" } */ +/* This is the vector version of these optimizations. */ +/* PR tree-optimization/19832 */ + +#define vector __attribute__((vector_size(sizeof(unsigned)*2))) + +static inline vector int max_(vector int a, vector int b) +{ + return (a > b)? a : b; +} +static inline vector int min_(vector int a, vector int b) +{ + return (a < b) ? a : b; +} + +vector int f_minus(vector int a, vector int b) +{ + return (a != b) ? a - b : (a - a); +} +vector int f_xor(vector int a, vector int b) +{ + return (a != b) ? a ^ b : (a ^ a); +} + +vector int f_ior(vector int a, vector int b) +{ + return (a != b) ? a | b : (a | a); +} +vector int f_and(vector int a, vector int b) +{ + return (a != b) ? a & b : (a & a); +} +vector int f_max(vector int a, vector int b) +{ + return (a != b) ? max_(a, b) : max_(a, a); +} +vector int f_min(vector int a, vector int b) +{ + return (a != b) ? min_(a, b) : min_(a, a); +} +vector int f_mult(vector int a, vector int b) +{ + return (a != b) ? a * b : (a * a); +} +vector int f_plus(vector int a, vector int b) +{ + return (a != b) ? a + b : (a + a); +} +vector int f_plus_alt(vector int a, vector int b) +{ + return (a != b) ? a + b : (a * 2); +} + +/* All of the above function's VEC_COND_EXPR should have been optimized away. */ +/* { dg-final { scan-tree-dump-not "VEC_COND_EXPR " "ccp1" } } */ +/* { dg-final { scan-tree-dump-not "VEC_COND_EXPR " "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-same-1.c b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-same-1.c new file mode 100644 index 00000000000..24e757b9b9f --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-same-1.c @@ -0,0 +1,60 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-phiopt1 -fdump-tree-optimized" } */ +/* PR tree-optimization/19832 */ + +static inline int max_(int a, int b) +{ + if (a > b) return a; + return b; +} +static inline int min_(int a, int b) +{ + if (a < b) return a; + return b; +} + +int f_minus(int a, int b) +{ + if (a != b) return a - b; + return a - a; +} +int f_xor(int a, int b) +{ + if (a != b) return a ^ b; + return a ^ a; +} + +int f_ior(int a, int b) +{ + if (a != b) return a | b; + return a | a; +} +int f_and(int a, int b) +{ + if (a != b) return a & b; + return a & a; +} +int f_max(int a, int b) +{ + if (a != b) return max_(a,b); + return max_(a,a); +} +int f_min(int a, int b) +{ + if (a != b) return min_(a,b); + return min_(a,a); +} +int f_mult(int a, int b) +{ + if (a != b) return a * b; + return a * a; +} +int f_plus(int a, int b) +{ + if (a != b) return a + b; + return a + a; +} + +/* All of the above function's if should have been optimized away even in phiopt1. */ +/* { dg-final { scan-tree-dump-not "if " "phiopt1" } } */ +/* { dg-final { scan-tree-dump-not "if " "optimized" } } */ -- 2.31.1