| Message ID | VI1PR0802MB21765169BC2A476EF7A6A9ADE7A80@VI1PR0802MB2176.eurprd08.prod.outlook.com |
|---|---|
| State | New |
| Headers | show |
On Tue, Oct 25, 2016 at 1:21 PM, Bin Cheng <Bin.Cheng@arm.com> wrote: > Hi, > This is a patch set adding various match.pd patterns in order to generate simplified MIN/MAX_EXPR mostly from COND_EXPR. This is the first one optimizing (convert1 (minmax ((convert2 (x) c)))) to minmax (x c), if convert2 promotes x and convert1 demotes back to x's type. With this patch, generated assembly for test: > .L4: > ldr q0, [x3, x1] > add w2, w2, 1 > cmp w0, w2 > ushll v2.4s, v0.4h, 0 > ushll2 v1.4s, v0.8h, 0 > umin v2.4s, v2.4s, v3.4s > umin v1.4s, v1.4s, v3.4s > xtn v4.4h, v2.4s > xtn2 v4.8h, v1.4s > str q4, [x3, x1] > add x1, x1, 16 > bhi .L4 > > can be improved to: > .L4: > ldr q0, [x3, x1] > add w2, w2, 1 > cmp w0, w2 > umin v1.8h, v0.8h, v2.8h > str q1, [x3, x1] > add x1, x1, 16 > bhi .L4 > > Bootstrap and test on x86_64 and AArch64 for whole patch set. Is it OK? Why restrict to GIMPLE? +/* (convert1 (minmax ((convert2 (x) c)))) -> minmax (x c) if convert2 + promotes x and convert1 demotes back to x's type. */ + +(for minmax (min max) + (simplify + (convert (minmax@0 (convert @1) INTEGER_CST@2)) + (if (types_compatible_p (TREE_TYPE (@1), type)) comment mentions convert1 and convert2, just convert is correct I think. Please use types_match instead of types_compatible_p, this is a wrapper that does the correct thing for both GENERIC and GIMPLE. + (with + { + tree minmax_type = TREE_TYPE (@0); + signop sgn = TYPE_SIGN (type); + widest_int type_min = widest_int::from (wi::min_value (type), sgn); + widest_int type_max = widest_int::from (wi::max_value (type), sgn); + } + (if (sgn == TYPE_SIGN (minmax_type) + && TYPE_PRECISION (minmax_type) >= TYPE_PRECISION (type) + && wi::to_widest (@2) >= type_min && wi::to_widest (@2) <= type_max) instead of this you can use int_fits_type_p (type, @2) + (minmax @1 { fold_convert (type, @2); })))))) use (minmax @1 (convert @2)) I believe the transform is also a win if @2 is not a constant but similarly promoted as @1. This slightly complicates the patter and thus can be done as followup (if we think it's useful at this point). With the simplification you should get rid of the with{} Thanks, Richard. > Thanks, > bin > > 2016-10-21 Bin Cheng <bin.cheng@arm.com> > > * match.pd ((convert1 (minmax ((convert2 (x) c)))) -> minmax (x c)): > New pattern. > > gcc/testsuite/ChangeLog > 2016-10-21 Bin Cheng <bin.cheng@arm.com> > > * gcc.dg/fold-convmaxconv-1.c: New test. > * gcc.dg/fold-convminconv-1.c: New test.
diff --git a/gcc/match.pd b/gcc/match.pd index b782a1e..7365bc1 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -1331,6 +1331,28 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) && TYPE_MIN_VALUE (type) && operand_equal_p (@1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST)) @0))) + +#if GIMPLE +/* (convert1 (minmax ((convert2 (x) c)))) -> minmax (x c) if convert2 + promotes x and convert1 demotes back to x's type. */ + +(for minmax (min max) + (simplify + (convert (minmax@0 (convert @1) INTEGER_CST@2)) + (if (types_compatible_p (TREE_TYPE (@1), type)) + (with + { + tree minmax_type = TREE_TYPE (@0); + signop sgn = TYPE_SIGN (type); + widest_int type_min = widest_int::from (wi::min_value (type), sgn); + widest_int type_max = widest_int::from (wi::max_value (type), sgn); + } + (if (sgn == TYPE_SIGN (minmax_type) + && TYPE_PRECISION (minmax_type) >= TYPE_PRECISION (type) + && wi::to_widest (@2) >= type_min && wi::to_widest (@2) <= type_max) + (minmax @1 { fold_convert (type, @2); })))))) +#endif + (for minmax (FMIN FMAX) /* If either argument is NaN, return the other one. Avoid the transformation if we get (and honor) a signalling NaN. */ diff --git a/gcc/testsuite/gcc.dg/fold-convmaxconv-1.c b/gcc/testsuite/gcc.dg/fold-convmaxconv-1.c new file mode 100644 index 0000000..3ffff8b --- /dev/null +++ b/gcc/testsuite/gcc.dg/fold-convmaxconv-1.c @@ -0,0 +1,15 @@ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-optimized" } */ + +int foo (short a[], int x) +{ + unsigned int i; + for (i = 0; i < 1000; i++) + { + x = a[i]; + a[i] = (x <= 0 ? 0 : x); + } + return x; +} + +/* { dg-final { scan-tree-dump-not " = MAX_EXPR <x_\[0-9\]*" "optimized" } } */ diff --git a/gcc/testsuite/gcc.dg/fold-convminconv-1.c b/gcc/testsuite/gcc.dg/fold-convminconv-1.c new file mode 100644 index 0000000..f4a048e --- /dev/null +++ b/gcc/testsuite/gcc.dg/fold-convminconv-1.c @@ -0,0 +1,15 @@ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-optimized" } */ + +int foo (unsigned short a[], unsigned int x) +{ + unsigned int i; + for (i = 0; i < 1000; i++) + { + x = a[i]; + a[i] = (x >= 255 ? 255 : x); + } + return x; +} + +/* { dg-final { scan-tree-dump-not " = MIN_EXPR <x_\[0-9\]*" "optimized" } } */