* [PATCH v3] Simplify memchr with small constant strings
@ 2022-07-13 16:50 H.J. Lu
2022-07-14 6:42 ` Richard Biener
2022-09-07 10:57 ` Jan-Benedict Glaw
0 siblings, 2 replies; 6+ messages in thread
From: H.J. Lu @ 2022-07-13 16:50 UTC (permalink / raw)
To: gcc-patches
When memchr is applied on a constant string of no more than the bytes of
a word, simplify memchr by checking each byte in the constant string.
int f (int a)
{
return __builtin_memchr ("AE", a, 2) != 0;
}
is simplified to
int f (int a)
{
return ((char) a == 'A' || (char) a == 'E') != 0;
}
gcc/
PR tree-optimization/103798
* tree-ssa-forwprop.cc: Include "tree-ssa-strlen.h".
(simplify_builtin_call): Inline memchr with constant strings of
no more than the bytes of a word.
* tree-ssa-strlen.cc (use_in_zero_equality): Make it global.
* tree-ssa-strlen.h (use_in_zero_equality): New.
gcc/testsuite/
PR tree-optimization/103798
* c-c++-common/pr103798-1.c: New test.
* c-c++-common/pr103798-2.c: Likewise.
* c-c++-common/pr103798-3.c: Likewise.
* c-c++-common/pr103798-4.c: Likewise.
* c-c++-common/pr103798-5.c: Likewise.
* c-c++-common/pr103798-6.c: Likewise.
* c-c++-common/pr103798-7.c: Likewise.
* c-c++-common/pr103798-8.c: Likewise.
* c-c++-common/pr103798-9.c: Likewise.
* c-c++-common/pr103798-10.c: Likewise.
---
gcc/testsuite/c-c++-common/pr103798-1.c | 28 +++++++++
gcc/testsuite/c-c++-common/pr103798-10.c | 10 ++++
gcc/testsuite/c-c++-common/pr103798-2.c | 30 ++++++++++
gcc/testsuite/c-c++-common/pr103798-3.c | 28 +++++++++
gcc/testsuite/c-c++-common/pr103798-4.c | 28 +++++++++
gcc/testsuite/c-c++-common/pr103798-5.c | 26 +++++++++
gcc/testsuite/c-c++-common/pr103798-6.c | 27 +++++++++
gcc/testsuite/c-c++-common/pr103798-7.c | 27 +++++++++
gcc/testsuite/c-c++-common/pr103798-8.c | 27 +++++++++
gcc/testsuite/c-c++-common/pr103798-9.c | 10 ++++
gcc/tree-ssa-forwprop.cc | 73 ++++++++++++++++++++++++
gcc/tree-ssa-strlen.cc | 4 +-
gcc/tree-ssa-strlen.h | 2 +
13 files changed, 318 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/c-c++-common/pr103798-1.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-10.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-2.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-3.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-4.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-5.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-6.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-7.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-8.c
create mode 100644 gcc/testsuite/c-c++-common/pr103798-9.c
diff --git a/gcc/testsuite/c-c++-common/pr103798-1.c b/gcc/testsuite/c-c++-common/pr103798-1.c
new file mode 100644
index 00000000000..cd3edf569fc
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-1.c
@@ -0,0 +1,28 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */
+
+__attribute__ ((weak))
+int
+f (char a)
+{
+ return __builtin_memchr ("a", a, 1) == 0;
+}
+
+__attribute__ ((weak))
+int
+g (char a)
+{
+ return a != 'a';
+}
+
+int
+main ()
+{
+ for (int i = 0; i < 255; i++)
+ if (f (i) != g (i))
+ __builtin_abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-10.c b/gcc/testsuite/c-c++-common/pr103798-10.c
new file mode 100644
index 00000000000..4677e9539fa
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-10.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-Os -fdump-tree-optimized -save-temps" } */
+
+int
+f (char a)
+{
+ return __builtin_memchr ("ac", a, 1) == 0;
+}
+
+/* { dg-final { scan-assembler "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-2.c b/gcc/testsuite/c-c++-common/pr103798-2.c
new file mode 100644
index 00000000000..e7e99c3679e
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-2.c
@@ -0,0 +1,30 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */
+
+#include <string.h>
+
+__attribute__ ((weak))
+int
+f (int a)
+{
+ return memchr ("aE", a, 2) != NULL;
+}
+
+__attribute__ ((weak))
+int
+g (char a)
+{
+ return a == 'a' || a == 'E';
+}
+
+int
+main ()
+{
+ for (int i = 0; i < 255; i++)
+ if (f (i + 256) != g (i + 256))
+ __builtin_abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-3.c b/gcc/testsuite/c-c++-common/pr103798-3.c
new file mode 100644
index 00000000000..ddcedc7e238
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-3.c
@@ -0,0 +1,28 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */
+
+__attribute__ ((weak))
+int
+f (char a)
+{
+ return __builtin_memchr ("aEgZ", a, 3) == 0;
+}
+
+__attribute__ ((weak))
+int
+g (char a)
+{
+ return a != 'a' && a != 'E' && a != 'g';
+}
+
+int
+main ()
+{
+ for (int i = 0; i < 255; i++)
+ if (f (i) != g (i))
+ __builtin_abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-4.c b/gcc/testsuite/c-c++-common/pr103798-4.c
new file mode 100644
index 00000000000..00e8302a833
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-4.c
@@ -0,0 +1,28 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */
+
+__attribute__ ((weak))
+int
+f (char a)
+{
+ return __builtin_memchr ("aEgi", a, 4) != 0;
+}
+
+__attribute__ ((weak))
+int
+g (char a)
+{
+ return a == 'a' || a == 'E' || a == 'g' || a == 'i';
+}
+
+int
+main ()
+{
+ for (int i = 0; i < 255; i++)
+ if (f (i) != g (i))
+ __builtin_abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-5.c b/gcc/testsuite/c-c++-common/pr103798-5.c
new file mode 100644
index 00000000000..0d6487a13df
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-5.c
@@ -0,0 +1,26 @@
+/* { dg-do run { target int128 } } */
+/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */
+
+__attribute__ ((weak))
+int f(char a)
+{
+ return __builtin_memchr ("aEgiH", a, 5) == 0;
+}
+
+__attribute__ ((weak))
+int g(char a)
+{
+ return a != 'a' && a != 'E' && a != 'g' && a != 'i' && a != 'H';
+}
+
+int
+main ()
+{
+ for (int i = 0; i < 255; i++)
+ if (f (i) != g (i))
+ __builtin_abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-6.c b/gcc/testsuite/c-c++-common/pr103798-6.c
new file mode 100644
index 00000000000..5ccb5ee66e0
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-6.c
@@ -0,0 +1,27 @@
+/* { dg-do run { target int128 } } */
+/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */
+
+__attribute__ ((weak))
+int f(char a)
+{
+ return __builtin_memchr ("aEgiHx", a, 6) != 0;
+}
+
+__attribute__ ((weak))
+int g(char a)
+{
+ return (a == 'a' || a == 'E' || a == 'g' || a == 'i' || a == 'H'
+ || a == 'x');
+}
+
+int
+main ()
+{
+ for (int i = 0; i < 255; i++)
+ if (f (i) != g (i))
+ __builtin_abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-7.c b/gcc/testsuite/c-c++-common/pr103798-7.c
new file mode 100644
index 00000000000..40fd38257d1
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-7.c
@@ -0,0 +1,27 @@
+/* { dg-do run { target int128 } } */
+/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */
+
+__attribute__ ((weak))
+int f(char a)
+{
+ return __builtin_memchr ("aEgiHjZ", a, 7) == 0;
+}
+
+__attribute__ ((weak))
+int g(char a)
+{
+ return (a != 'a' && a != 'E' && a != 'g' && a != 'i' && a != 'H'
+ && a != 'j' && a != 'Z');
+}
+
+int
+main ()
+{
+ for (int i = 0; i < 255; i++)
+ if (f (i) != g (i))
+ __builtin_abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-8.c b/gcc/testsuite/c-c++-common/pr103798-8.c
new file mode 100644
index 00000000000..0841b18cea4
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-8.c
@@ -0,0 +1,27 @@
+/* { dg-do run { target int128 } } */
+/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */
+
+__attribute__ ((weak))
+int f(int a)
+{
+ return __builtin_memchr ("aEgiHx19ABC", a, 8) != 0;
+}
+
+__attribute__ ((weak))
+int g(char a)
+{
+ return (a == 'a' || a == 'E' || a == 'g' || a == 'i' || a == 'H'
+ || a == 'x' || a == '1' || a == '9');
+}
+
+int
+main ()
+{
+ for (int i = 0; i < 255; i++)
+ if (f (i + 256) != g (i + 256))
+ __builtin_abort ();
+
+ return 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/testsuite/c-c++-common/pr103798-9.c b/gcc/testsuite/c-c++-common/pr103798-9.c
new file mode 100644
index 00000000000..c5f0f94a4b5
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr103798-9.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-Os -fdump-tree-optimized -save-temps" } */
+
+int
+f (char a)
+{
+ return __builtin_memchr ("a", a, 1) == 0;
+}
+
+/* { dg-final { scan-assembler-not "memchr" } } */
diff --git a/gcc/tree-ssa-forwprop.cc b/gcc/tree-ssa-forwprop.cc
index 69567ab3275..28549c85f76 100644
--- a/gcc/tree-ssa-forwprop.cc
+++ b/gcc/tree-ssa-forwprop.cc
@@ -42,6 +42,7 @@ along with GCC; see the file COPYING3. If not see
#include "tree-dfa.h"
#include "tree-ssa-propagate.h"
#include "tree-ssa-dom.h"
+#include "tree-ssa-strlen.h"
#include "builtins.h"
#include "tree-cfgcleanup.h"
#include "cfganal.h"
@@ -1177,6 +1178,15 @@ constant_pointer_difference (tree p1, tree p2)
memcpy (p, "abcd ", 7);
call if the latter can be stored by pieces during expansion.
+ Optimize
+ memchr ("abcd", a, 4) == 0;
+ or
+ memchr ("abcd", a, 4) != 0;
+ to
+ (a == 'a' || a == 'b' || a == 'c' || a == 'd') == 0
+ or
+ (a == 'a' || a == 'b' || a == 'c' || a == 'd') != 0
+
Also canonicalize __atomic_fetch_op (p, x, y) op x
to __atomic_op_fetch (p, x, y) or
__atomic_op_fetch (p, x, y) iop x
@@ -1193,8 +1203,71 @@ simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2)
return false;
stmt1 = SSA_NAME_DEF_STMT (vuse);
+ tree res;
+
switch (DECL_FUNCTION_CODE (callee2))
{
+ case BUILT_IN_MEMCHR:
+ if (gimple_call_num_args (stmt2) == 3
+ && (res = gimple_call_lhs (stmt2)) != nullptr
+ && use_in_zero_equality (res) != nullptr
+ && CHAR_BIT == 8
+ && BITS_PER_UNIT == 8)
+ {
+ tree ptr = gimple_call_arg (stmt2, 0);
+ if (TREE_CODE (ptr) != ADDR_EXPR
+ || TREE_CODE (TREE_OPERAND (ptr, 0)) != STRING_CST)
+ break;
+ unsigned HOST_WIDE_INT slen
+ = TREE_STRING_LENGTH (TREE_OPERAND (ptr, 0));
+ /* It must be a non-empty string constant. */
+ if (slen < 2)
+ break;
+ /* For -Os, only simplify strings with a single character. */
+ if (!optimize_bb_for_speed_p (gimple_bb (stmt2))
+ && slen > 2)
+ break;
+ tree size = gimple_call_arg (stmt2, 2);
+ /* Size must be a constant which is <= UNITS_PER_WORD and
+ <= the string length. */
+ if (TREE_CODE (size) != INTEGER_CST || integer_zerop (size))
+ break;
+
+ if (!tree_fits_uhwi_p (size))
+ break;
+
+ unsigned HOST_WIDE_INT sz = tree_to_uhwi (size);
+ if (sz > UNITS_PER_WORD || sz >= slen)
+ break;
+
+ tree ch = gimple_call_arg (stmt2, 1);
+ location_t loc = gimple_location (stmt2);
+ if (!useless_type_conversion_p (char_type_node,
+ TREE_TYPE (ch)))
+ ch = fold_convert_loc (loc, char_type_node, ch);
+ const char *p = TREE_STRING_POINTER (TREE_OPERAND (ptr, 0));
+ unsigned int isize = sz;
+ tree *op = new tree[isize];
+ for (unsigned int i = 0; i < isize; i++)
+ {
+ op[i] = build_int_cst (char_type_node, p[i]);
+ op[i] = fold_build2_loc (loc, EQ_EXPR, boolean_type_node,
+ op[i], ch);
+ }
+ for (unsigned int i = isize - 1; i >= 1; i--)
+ op[i - 1] = fold_convert_loc (loc, boolean_type_node,
+ fold_build2_loc (loc,
+ BIT_IOR_EXPR,
+ boolean_type_node,
+ op[i - 1],
+ op[i]));
+ res = fold_convert_loc (loc, TREE_TYPE (res), op[0]);
+ gimplify_and_update_call_from_tree (gsi_p, res);
+ delete[] op;
+ return true;
+ }
+ break;
+
case BUILT_IN_MEMSET:
if (gimple_call_num_args (stmt2) != 3
|| gimple_call_lhs (stmt2)
diff --git a/gcc/tree-ssa-strlen.cc b/gcc/tree-ssa-strlen.cc
index 7b3e3899ea2..5afbae1b72e 100644
--- a/gcc/tree-ssa-strlen.cc
+++ b/gcc/tree-ssa-strlen.cc
@@ -3913,8 +3913,8 @@ strlen_pass::handle_builtin_memset (bool *zero_write)
nonnull if and only RES is used in such expressions exclusively and
in none other. */
-static gimple *
-use_in_zero_equality (tree res, bool exclusive = true)
+gimple *
+use_in_zero_equality (tree res, bool exclusive)
{
gimple *first_use = NULL;
diff --git a/gcc/tree-ssa-strlen.h b/gcc/tree-ssa-strlen.h
index 8d155450db8..fdb4d9d7783 100644
--- a/gcc/tree-ssa-strlen.h
+++ b/gcc/tree-ssa-strlen.h
@@ -35,6 +35,8 @@ struct c_strlen_data;
extern void get_range_strlen_dynamic (tree, gimple *, c_strlen_data *,
pointer_query &);
+extern gimple *use_in_zero_equality (tree, bool = true);
+
/* APIs internal to strlen pass. Defined in gimple-ssa-sprintf.cc. */
extern bool handle_printf_call (gimple_stmt_iterator *, pointer_query &);
--
2.36.1
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v3] Simplify memchr with small constant strings 2022-07-13 16:50 [PATCH v3] Simplify memchr with small constant strings H.J. Lu @ 2022-07-14 6:42 ` Richard Biener 2022-07-14 21:09 ` H.J. Lu 2022-09-07 10:57 ` Jan-Benedict Glaw 1 sibling, 1 reply; 6+ messages in thread From: Richard Biener @ 2022-07-14 6:42 UTC (permalink / raw) To: H.J. Lu; +Cc: GCC Patches On Wed, Jul 13, 2022 at 6:50 PM H.J. Lu <hjl.tools@gmail.com> wrote: > > When memchr is applied on a constant string of no more than the bytes of > a word, simplify memchr by checking each byte in the constant string. > > int f (int a) > { > return __builtin_memchr ("AE", a, 2) != 0; > } > > is simplified to > > int f (int a) > { > return ((char) a == 'A' || (char) a == 'E') != 0; > } > > gcc/ > > PR tree-optimization/103798 > * tree-ssa-forwprop.cc: Include "tree-ssa-strlen.h". > (simplify_builtin_call): Inline memchr with constant strings of > no more than the bytes of a word. > * tree-ssa-strlen.cc (use_in_zero_equality): Make it global. > * tree-ssa-strlen.h (use_in_zero_equality): New. > > gcc/testsuite/ > > PR tree-optimization/103798 > * c-c++-common/pr103798-1.c: New test. > * c-c++-common/pr103798-2.c: Likewise. > * c-c++-common/pr103798-3.c: Likewise. > * c-c++-common/pr103798-4.c: Likewise. > * c-c++-common/pr103798-5.c: Likewise. > * c-c++-common/pr103798-6.c: Likewise. > * c-c++-common/pr103798-7.c: Likewise. > * c-c++-common/pr103798-8.c: Likewise. > * c-c++-common/pr103798-9.c: Likewise. > * c-c++-common/pr103798-10.c: Likewise. > --- > gcc/testsuite/c-c++-common/pr103798-1.c | 28 +++++++++ > gcc/testsuite/c-c++-common/pr103798-10.c | 10 ++++ > gcc/testsuite/c-c++-common/pr103798-2.c | 30 ++++++++++ > gcc/testsuite/c-c++-common/pr103798-3.c | 28 +++++++++ > gcc/testsuite/c-c++-common/pr103798-4.c | 28 +++++++++ > gcc/testsuite/c-c++-common/pr103798-5.c | 26 +++++++++ > gcc/testsuite/c-c++-common/pr103798-6.c | 27 +++++++++ > gcc/testsuite/c-c++-common/pr103798-7.c | 27 +++++++++ > gcc/testsuite/c-c++-common/pr103798-8.c | 27 +++++++++ > gcc/testsuite/c-c++-common/pr103798-9.c | 10 ++++ > gcc/tree-ssa-forwprop.cc | 73 ++++++++++++++++++++++++ > gcc/tree-ssa-strlen.cc | 4 +- > gcc/tree-ssa-strlen.h | 2 + > 13 files changed, 318 insertions(+), 2 deletions(-) > create mode 100644 gcc/testsuite/c-c++-common/pr103798-1.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-10.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-2.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-3.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-4.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-5.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-6.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-7.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-8.c > create mode 100644 gcc/testsuite/c-c++-common/pr103798-9.c > > diff --git a/gcc/testsuite/c-c++-common/pr103798-1.c b/gcc/testsuite/c-c++-common/pr103798-1.c > new file mode 100644 > index 00000000000..cd3edf569fc > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-1.c > @@ -0,0 +1,28 @@ > +/* { dg-do run } */ > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > + > +__attribute__ ((weak)) > +int > +f (char a) > +{ > + return __builtin_memchr ("a", a, 1) == 0; > +} > + > +__attribute__ ((weak)) > +int > +g (char a) > +{ > + return a != 'a'; > +} > + > +int > +main () > +{ > + for (int i = 0; i < 255; i++) > + if (f (i) != g (i)) > + __builtin_abort (); > + > + return 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-10.c b/gcc/testsuite/c-c++-common/pr103798-10.c > new file mode 100644 > index 00000000000..4677e9539fa > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-10.c > @@ -0,0 +1,10 @@ > +/* { dg-do compile } */ > +/* { dg-options "-Os -fdump-tree-optimized -save-temps" } */ > + > +int > +f (char a) > +{ > + return __builtin_memchr ("ac", a, 1) == 0; > +} > + > +/* { dg-final { scan-assembler "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-2.c b/gcc/testsuite/c-c++-common/pr103798-2.c > new file mode 100644 > index 00000000000..e7e99c3679e > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-2.c > @@ -0,0 +1,30 @@ > +/* { dg-do run } */ > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > + > +#include <string.h> > + > +__attribute__ ((weak)) > +int > +f (int a) > +{ > + return memchr ("aE", a, 2) != NULL; > +} > + > +__attribute__ ((weak)) > +int > +g (char a) > +{ > + return a == 'a' || a == 'E'; > +} > + > +int > +main () > +{ > + for (int i = 0; i < 255; i++) > + if (f (i + 256) != g (i + 256)) > + __builtin_abort (); > + > + return 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-3.c b/gcc/testsuite/c-c++-common/pr103798-3.c > new file mode 100644 > index 00000000000..ddcedc7e238 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-3.c > @@ -0,0 +1,28 @@ > +/* { dg-do run } */ > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > + > +__attribute__ ((weak)) > +int > +f (char a) > +{ > + return __builtin_memchr ("aEgZ", a, 3) == 0; > +} > + > +__attribute__ ((weak)) > +int > +g (char a) > +{ > + return a != 'a' && a != 'E' && a != 'g'; > +} > + > +int > +main () > +{ > + for (int i = 0; i < 255; i++) > + if (f (i) != g (i)) > + __builtin_abort (); > + > + return 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-4.c b/gcc/testsuite/c-c++-common/pr103798-4.c > new file mode 100644 > index 00000000000..00e8302a833 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-4.c > @@ -0,0 +1,28 @@ > +/* { dg-do run } */ > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > + > +__attribute__ ((weak)) > +int > +f (char a) > +{ > + return __builtin_memchr ("aEgi", a, 4) != 0; > +} > + > +__attribute__ ((weak)) > +int > +g (char a) > +{ > + return a == 'a' || a == 'E' || a == 'g' || a == 'i'; > +} > + > +int > +main () > +{ > + for (int i = 0; i < 255; i++) > + if (f (i) != g (i)) > + __builtin_abort (); > + > + return 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-5.c b/gcc/testsuite/c-c++-common/pr103798-5.c > new file mode 100644 > index 00000000000..0d6487a13df > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-5.c > @@ -0,0 +1,26 @@ > +/* { dg-do run { target int128 } } */ > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > + > +__attribute__ ((weak)) > +int f(char a) > +{ > + return __builtin_memchr ("aEgiH", a, 5) == 0; > +} > + > +__attribute__ ((weak)) > +int g(char a) > +{ > + return a != 'a' && a != 'E' && a != 'g' && a != 'i' && a != 'H'; > +} > + > +int > +main () > +{ > + for (int i = 0; i < 255; i++) > + if (f (i) != g (i)) > + __builtin_abort (); > + > + return 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-6.c b/gcc/testsuite/c-c++-common/pr103798-6.c > new file mode 100644 > index 00000000000..5ccb5ee66e0 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-6.c > @@ -0,0 +1,27 @@ > +/* { dg-do run { target int128 } } */ > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > + > +__attribute__ ((weak)) > +int f(char a) > +{ > + return __builtin_memchr ("aEgiHx", a, 6) != 0; > +} > + > +__attribute__ ((weak)) > +int g(char a) > +{ > + return (a == 'a' || a == 'E' || a == 'g' || a == 'i' || a == 'H' > + || a == 'x'); > +} > + > +int > +main () > +{ > + for (int i = 0; i < 255; i++) > + if (f (i) != g (i)) > + __builtin_abort (); > + > + return 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-7.c b/gcc/testsuite/c-c++-common/pr103798-7.c > new file mode 100644 > index 00000000000..40fd38257d1 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-7.c > @@ -0,0 +1,27 @@ > +/* { dg-do run { target int128 } } */ > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > + > +__attribute__ ((weak)) > +int f(char a) > +{ > + return __builtin_memchr ("aEgiHjZ", a, 7) == 0; > +} > + > +__attribute__ ((weak)) > +int g(char a) > +{ > + return (a != 'a' && a != 'E' && a != 'g' && a != 'i' && a != 'H' > + && a != 'j' && a != 'Z'); > +} > + > +int > +main () > +{ > + for (int i = 0; i < 255; i++) > + if (f (i) != g (i)) > + __builtin_abort (); > + > + return 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-8.c b/gcc/testsuite/c-c++-common/pr103798-8.c > new file mode 100644 > index 00000000000..0841b18cea4 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-8.c > @@ -0,0 +1,27 @@ > +/* { dg-do run { target int128 } } */ > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > + > +__attribute__ ((weak)) > +int f(int a) > +{ > + return __builtin_memchr ("aEgiHx19ABC", a, 8) != 0; > +} > + > +__attribute__ ((weak)) > +int g(char a) > +{ > + return (a == 'a' || a == 'E' || a == 'g' || a == 'i' || a == 'H' > + || a == 'x' || a == '1' || a == '9'); > +} > + > +int > +main () > +{ > + for (int i = 0; i < 255; i++) > + if (f (i + 256) != g (i + 256)) > + __builtin_abort (); > + > + return 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/testsuite/c-c++-common/pr103798-9.c b/gcc/testsuite/c-c++-common/pr103798-9.c > new file mode 100644 > index 00000000000..c5f0f94a4b5 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/pr103798-9.c > @@ -0,0 +1,10 @@ > +/* { dg-do compile } */ > +/* { dg-options "-Os -fdump-tree-optimized -save-temps" } */ > + > +int > +f (char a) > +{ > + return __builtin_memchr ("a", a, 1) == 0; > +} > + > +/* { dg-final { scan-assembler-not "memchr" } } */ > diff --git a/gcc/tree-ssa-forwprop.cc b/gcc/tree-ssa-forwprop.cc > index 69567ab3275..28549c85f76 100644 > --- a/gcc/tree-ssa-forwprop.cc > +++ b/gcc/tree-ssa-forwprop.cc > @@ -42,6 +42,7 @@ along with GCC; see the file COPYING3. If not see > #include "tree-dfa.h" > #include "tree-ssa-propagate.h" > #include "tree-ssa-dom.h" > +#include "tree-ssa-strlen.h" > #include "builtins.h" > #include "tree-cfgcleanup.h" > #include "cfganal.h" > @@ -1177,6 +1178,15 @@ constant_pointer_difference (tree p1, tree p2) > memcpy (p, "abcd ", 7); > call if the latter can be stored by pieces during expansion. > > + Optimize > + memchr ("abcd", a, 4) == 0; > + or > + memchr ("abcd", a, 4) != 0; > + to > + (a == 'a' || a == 'b' || a == 'c' || a == 'd') == 0 > + or > + (a == 'a' || a == 'b' || a == 'c' || a == 'd') != 0 > + > Also canonicalize __atomic_fetch_op (p, x, y) op x > to __atomic_op_fetch (p, x, y) or > __atomic_op_fetch (p, x, y) iop x > @@ -1193,8 +1203,71 @@ simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2) > return false; > stmt1 = SSA_NAME_DEF_STMT (vuse); > > + tree res; > + > switch (DECL_FUNCTION_CODE (callee2)) > { > + case BUILT_IN_MEMCHR: > + if (gimple_call_num_args (stmt2) == 3 > + && (res = gimple_call_lhs (stmt2)) != nullptr > + && use_in_zero_equality (res) != nullptr > + && CHAR_BIT == 8 > + && BITS_PER_UNIT == 8) > + { > + tree ptr = gimple_call_arg (stmt2, 0); > + if (TREE_CODE (ptr) != ADDR_EXPR > + || TREE_CODE (TREE_OPERAND (ptr, 0)) != STRING_CST) > + break; > + unsigned HOST_WIDE_INT slen > + = TREE_STRING_LENGTH (TREE_OPERAND (ptr, 0)); > + /* It must be a non-empty string constant. */ > + if (slen < 2) > + break; > + /* For -Os, only simplify strings with a single character. */ > + if (!optimize_bb_for_speed_p (gimple_bb (stmt2)) > + && slen > 2) > + break; > + tree size = gimple_call_arg (stmt2, 2); > + /* Size must be a constant which is <= UNITS_PER_WORD and > + <= the string length. */ > + if (TREE_CODE (size) != INTEGER_CST || integer_zerop (size)) > + break; > + > + if (!tree_fits_uhwi_p (size)) > + break; > + > + unsigned HOST_WIDE_INT sz = tree_to_uhwi (size); > + if (sz > UNITS_PER_WORD || sz >= slen) > + break; > + > + tree ch = gimple_call_arg (stmt2, 1); > + location_t loc = gimple_location (stmt2); > + if (!useless_type_conversion_p (char_type_node, > + TREE_TYPE (ch))) > + ch = fold_convert_loc (loc, char_type_node, ch); > + const char *p = TREE_STRING_POINTER (TREE_OPERAND (ptr, 0)); > + unsigned int isize = sz; > + tree *op = new tree[isize]; minor nit - sorry for not spotting earlier. Please use tree *op = XALLOCAVEC (tree, isize); Ok with that change. Richard. > + for (unsigned int i = 0; i < isize; i++) > + { > + op[i] = build_int_cst (char_type_node, p[i]); > + op[i] = fold_build2_loc (loc, EQ_EXPR, boolean_type_node, > + op[i], ch); > + } > + for (unsigned int i = isize - 1; i >= 1; i--) > + op[i - 1] = fold_convert_loc (loc, boolean_type_node, > + fold_build2_loc (loc, > + BIT_IOR_EXPR, > + boolean_type_node, > + op[i - 1], > + op[i])); > + res = fold_convert_loc (loc, TREE_TYPE (res), op[0]); > + gimplify_and_update_call_from_tree (gsi_p, res); > + delete[] op; > + return true; > + } > + break; > + > case BUILT_IN_MEMSET: > if (gimple_call_num_args (stmt2) != 3 > || gimple_call_lhs (stmt2) > diff --git a/gcc/tree-ssa-strlen.cc b/gcc/tree-ssa-strlen.cc > index 7b3e3899ea2..5afbae1b72e 100644 > --- a/gcc/tree-ssa-strlen.cc > +++ b/gcc/tree-ssa-strlen.cc > @@ -3913,8 +3913,8 @@ strlen_pass::handle_builtin_memset (bool *zero_write) > nonnull if and only RES is used in such expressions exclusively and > in none other. */ > > -static gimple * > -use_in_zero_equality (tree res, bool exclusive = true) > +gimple * > +use_in_zero_equality (tree res, bool exclusive) > { > gimple *first_use = NULL; > > diff --git a/gcc/tree-ssa-strlen.h b/gcc/tree-ssa-strlen.h > index 8d155450db8..fdb4d9d7783 100644 > --- a/gcc/tree-ssa-strlen.h > +++ b/gcc/tree-ssa-strlen.h > @@ -35,6 +35,8 @@ struct c_strlen_data; > extern void get_range_strlen_dynamic (tree, gimple *, c_strlen_data *, > pointer_query &); > > +extern gimple *use_in_zero_equality (tree, bool = true); > + > /* APIs internal to strlen pass. Defined in gimple-ssa-sprintf.cc. */ > extern bool handle_printf_call (gimple_stmt_iterator *, pointer_query &); > > -- > 2.36.1 > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3] Simplify memchr with small constant strings 2022-07-14 6:42 ` Richard Biener @ 2022-07-14 21:09 ` H.J. Lu 0 siblings, 0 replies; 6+ messages in thread From: H.J. Lu @ 2022-07-14 21:09 UTC (permalink / raw) To: Richard Biener; +Cc: GCC Patches [-- Attachment #1: Type: text/plain, Size: 16298 bytes --] On Wed, Jul 13, 2022 at 11:42 PM Richard Biener <richard.guenther@gmail.com> wrote: > > On Wed, Jul 13, 2022 at 6:50 PM H.J. Lu <hjl.tools@gmail.com> wrote: > > > > When memchr is applied on a constant string of no more than the bytes of > > a word, simplify memchr by checking each byte in the constant string. > > > > int f (int a) > > { > > return __builtin_memchr ("AE", a, 2) != 0; > > } > > > > is simplified to > > > > int f (int a) > > { > > return ((char) a == 'A' || (char) a == 'E') != 0; > > } > > > > gcc/ > > > > PR tree-optimization/103798 > > * tree-ssa-forwprop.cc: Include "tree-ssa-strlen.h". > > (simplify_builtin_call): Inline memchr with constant strings of > > no more than the bytes of a word. > > * tree-ssa-strlen.cc (use_in_zero_equality): Make it global. > > * tree-ssa-strlen.h (use_in_zero_equality): New. > > > > gcc/testsuite/ > > > > PR tree-optimization/103798 > > * c-c++-common/pr103798-1.c: New test. > > * c-c++-common/pr103798-2.c: Likewise. > > * c-c++-common/pr103798-3.c: Likewise. > > * c-c++-common/pr103798-4.c: Likewise. > > * c-c++-common/pr103798-5.c: Likewise. > > * c-c++-common/pr103798-6.c: Likewise. > > * c-c++-common/pr103798-7.c: Likewise. > > * c-c++-common/pr103798-8.c: Likewise. > > * c-c++-common/pr103798-9.c: Likewise. > > * c-c++-common/pr103798-10.c: Likewise. > > --- > > gcc/testsuite/c-c++-common/pr103798-1.c | 28 +++++++++ > > gcc/testsuite/c-c++-common/pr103798-10.c | 10 ++++ > > gcc/testsuite/c-c++-common/pr103798-2.c | 30 ++++++++++ > > gcc/testsuite/c-c++-common/pr103798-3.c | 28 +++++++++ > > gcc/testsuite/c-c++-common/pr103798-4.c | 28 +++++++++ > > gcc/testsuite/c-c++-common/pr103798-5.c | 26 +++++++++ > > gcc/testsuite/c-c++-common/pr103798-6.c | 27 +++++++++ > > gcc/testsuite/c-c++-common/pr103798-7.c | 27 +++++++++ > > gcc/testsuite/c-c++-common/pr103798-8.c | 27 +++++++++ > > gcc/testsuite/c-c++-common/pr103798-9.c | 10 ++++ > > gcc/tree-ssa-forwprop.cc | 73 ++++++++++++++++++++++++ > > gcc/tree-ssa-strlen.cc | 4 +- > > gcc/tree-ssa-strlen.h | 2 + > > 13 files changed, 318 insertions(+), 2 deletions(-) > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-1.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-10.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-2.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-3.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-4.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-5.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-6.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-7.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-8.c > > create mode 100644 gcc/testsuite/c-c++-common/pr103798-9.c > > > > diff --git a/gcc/testsuite/c-c++-common/pr103798-1.c b/gcc/testsuite/c-c++-common/pr103798-1.c > > new file mode 100644 > > index 00000000000..cd3edf569fc > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-1.c > > @@ -0,0 +1,28 @@ > > +/* { dg-do run } */ > > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > > + > > +__attribute__ ((weak)) > > +int > > +f (char a) > > +{ > > + return __builtin_memchr ("a", a, 1) == 0; > > +} > > + > > +__attribute__ ((weak)) > > +int > > +g (char a) > > +{ > > + return a != 'a'; > > +} > > + > > +int > > +main () > > +{ > > + for (int i = 0; i < 255; i++) > > + if (f (i) != g (i)) > > + __builtin_abort (); > > + > > + return 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-10.c b/gcc/testsuite/c-c++-common/pr103798-10.c > > new file mode 100644 > > index 00000000000..4677e9539fa > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-10.c > > @@ -0,0 +1,10 @@ > > +/* { dg-do compile } */ > > +/* { dg-options "-Os -fdump-tree-optimized -save-temps" } */ > > + > > +int > > +f (char a) > > +{ > > + return __builtin_memchr ("ac", a, 1) == 0; > > +} > > + > > +/* { dg-final { scan-assembler "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-2.c b/gcc/testsuite/c-c++-common/pr103798-2.c > > new file mode 100644 > > index 00000000000..e7e99c3679e > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-2.c > > @@ -0,0 +1,30 @@ > > +/* { dg-do run } */ > > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > > + > > +#include <string.h> > > + > > +__attribute__ ((weak)) > > +int > > +f (int a) > > +{ > > + return memchr ("aE", a, 2) != NULL; > > +} > > + > > +__attribute__ ((weak)) > > +int > > +g (char a) > > +{ > > + return a == 'a' || a == 'E'; > > +} > > + > > +int > > +main () > > +{ > > + for (int i = 0; i < 255; i++) > > + if (f (i + 256) != g (i + 256)) > > + __builtin_abort (); > > + > > + return 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-3.c b/gcc/testsuite/c-c++-common/pr103798-3.c > > new file mode 100644 > > index 00000000000..ddcedc7e238 > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-3.c > > @@ -0,0 +1,28 @@ > > +/* { dg-do run } */ > > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > > + > > +__attribute__ ((weak)) > > +int > > +f (char a) > > +{ > > + return __builtin_memchr ("aEgZ", a, 3) == 0; > > +} > > + > > +__attribute__ ((weak)) > > +int > > +g (char a) > > +{ > > + return a != 'a' && a != 'E' && a != 'g'; > > +} > > + > > +int > > +main () > > +{ > > + for (int i = 0; i < 255; i++) > > + if (f (i) != g (i)) > > + __builtin_abort (); > > + > > + return 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-4.c b/gcc/testsuite/c-c++-common/pr103798-4.c > > new file mode 100644 > > index 00000000000..00e8302a833 > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-4.c > > @@ -0,0 +1,28 @@ > > +/* { dg-do run } */ > > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > > + > > +__attribute__ ((weak)) > > +int > > +f (char a) > > +{ > > + return __builtin_memchr ("aEgi", a, 4) != 0; > > +} > > + > > +__attribute__ ((weak)) > > +int > > +g (char a) > > +{ > > + return a == 'a' || a == 'E' || a == 'g' || a == 'i'; > > +} > > + > > +int > > +main () > > +{ > > + for (int i = 0; i < 255; i++) > > + if (f (i) != g (i)) > > + __builtin_abort (); > > + > > + return 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-5.c b/gcc/testsuite/c-c++-common/pr103798-5.c > > new file mode 100644 > > index 00000000000..0d6487a13df > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-5.c > > @@ -0,0 +1,26 @@ > > +/* { dg-do run { target int128 } } */ > > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > > + > > +__attribute__ ((weak)) > > +int f(char a) > > +{ > > + return __builtin_memchr ("aEgiH", a, 5) == 0; > > +} > > + > > +__attribute__ ((weak)) > > +int g(char a) > > +{ > > + return a != 'a' && a != 'E' && a != 'g' && a != 'i' && a != 'H'; > > +} > > + > > +int > > +main () > > +{ > > + for (int i = 0; i < 255; i++) > > + if (f (i) != g (i)) > > + __builtin_abort (); > > + > > + return 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-6.c b/gcc/testsuite/c-c++-common/pr103798-6.c > > new file mode 100644 > > index 00000000000..5ccb5ee66e0 > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-6.c > > @@ -0,0 +1,27 @@ > > +/* { dg-do run { target int128 } } */ > > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > > + > > +__attribute__ ((weak)) > > +int f(char a) > > +{ > > + return __builtin_memchr ("aEgiHx", a, 6) != 0; > > +} > > + > > +__attribute__ ((weak)) > > +int g(char a) > > +{ > > + return (a == 'a' || a == 'E' || a == 'g' || a == 'i' || a == 'H' > > + || a == 'x'); > > +} > > + > > +int > > +main () > > +{ > > + for (int i = 0; i < 255; i++) > > + if (f (i) != g (i)) > > + __builtin_abort (); > > + > > + return 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-7.c b/gcc/testsuite/c-c++-common/pr103798-7.c > > new file mode 100644 > > index 00000000000..40fd38257d1 > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-7.c > > @@ -0,0 +1,27 @@ > > +/* { dg-do run { target int128 } } */ > > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > > + > > +__attribute__ ((weak)) > > +int f(char a) > > +{ > > + return __builtin_memchr ("aEgiHjZ", a, 7) == 0; > > +} > > + > > +__attribute__ ((weak)) > > +int g(char a) > > +{ > > + return (a != 'a' && a != 'E' && a != 'g' && a != 'i' && a != 'H' > > + && a != 'j' && a != 'Z'); > > +} > > + > > +int > > +main () > > +{ > > + for (int i = 0; i < 255; i++) > > + if (f (i) != g (i)) > > + __builtin_abort (); > > + > > + return 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-8.c b/gcc/testsuite/c-c++-common/pr103798-8.c > > new file mode 100644 > > index 00000000000..0841b18cea4 > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-8.c > > @@ -0,0 +1,27 @@ > > +/* { dg-do run { target int128 } } */ > > +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ > > + > > +__attribute__ ((weak)) > > +int f(int a) > > +{ > > + return __builtin_memchr ("aEgiHx19ABC", a, 8) != 0; > > +} > > + > > +__attribute__ ((weak)) > > +int g(char a) > > +{ > > + return (a == 'a' || a == 'E' || a == 'g' || a == 'i' || a == 'H' > > + || a == 'x' || a == '1' || a == '9'); > > +} > > + > > +int > > +main () > > +{ > > + for (int i = 0; i < 255; i++) > > + if (f (i + 256) != g (i + 256)) > > + __builtin_abort (); > > + > > + return 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/testsuite/c-c++-common/pr103798-9.c b/gcc/testsuite/c-c++-common/pr103798-9.c > > new file mode 100644 > > index 00000000000..c5f0f94a4b5 > > --- /dev/null > > +++ b/gcc/testsuite/c-c++-common/pr103798-9.c > > @@ -0,0 +1,10 @@ > > +/* { dg-do compile } */ > > +/* { dg-options "-Os -fdump-tree-optimized -save-temps" } */ > > + > > +int > > +f (char a) > > +{ > > + return __builtin_memchr ("a", a, 1) == 0; > > +} > > + > > +/* { dg-final { scan-assembler-not "memchr" } } */ > > diff --git a/gcc/tree-ssa-forwprop.cc b/gcc/tree-ssa-forwprop.cc > > index 69567ab3275..28549c85f76 100644 > > --- a/gcc/tree-ssa-forwprop.cc > > +++ b/gcc/tree-ssa-forwprop.cc > > @@ -42,6 +42,7 @@ along with GCC; see the file COPYING3. If not see > > #include "tree-dfa.h" > > #include "tree-ssa-propagate.h" > > #include "tree-ssa-dom.h" > > +#include "tree-ssa-strlen.h" > > #include "builtins.h" > > #include "tree-cfgcleanup.h" > > #include "cfganal.h" > > @@ -1177,6 +1178,15 @@ constant_pointer_difference (tree p1, tree p2) > > memcpy (p, "abcd ", 7); > > call if the latter can be stored by pieces during expansion. > > > > + Optimize > > + memchr ("abcd", a, 4) == 0; > > + or > > + memchr ("abcd", a, 4) != 0; > > + to > > + (a == 'a' || a == 'b' || a == 'c' || a == 'd') == 0 > > + or > > + (a == 'a' || a == 'b' || a == 'c' || a == 'd') != 0 > > + > > Also canonicalize __atomic_fetch_op (p, x, y) op x > > to __atomic_op_fetch (p, x, y) or > > __atomic_op_fetch (p, x, y) iop x > > @@ -1193,8 +1203,71 @@ simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2) > > return false; > > stmt1 = SSA_NAME_DEF_STMT (vuse); > > > > + tree res; > > + > > switch (DECL_FUNCTION_CODE (callee2)) > > { > > + case BUILT_IN_MEMCHR: > > + if (gimple_call_num_args (stmt2) == 3 > > + && (res = gimple_call_lhs (stmt2)) != nullptr > > + && use_in_zero_equality (res) != nullptr > > + && CHAR_BIT == 8 > > + && BITS_PER_UNIT == 8) > > + { > > + tree ptr = gimple_call_arg (stmt2, 0); > > + if (TREE_CODE (ptr) != ADDR_EXPR > > + || TREE_CODE (TREE_OPERAND (ptr, 0)) != STRING_CST) > > + break; > > + unsigned HOST_WIDE_INT slen > > + = TREE_STRING_LENGTH (TREE_OPERAND (ptr, 0)); > > + /* It must be a non-empty string constant. */ > > + if (slen < 2) > > + break; > > + /* For -Os, only simplify strings with a single character. */ > > + if (!optimize_bb_for_speed_p (gimple_bb (stmt2)) > > + && slen > 2) > > + break; > > + tree size = gimple_call_arg (stmt2, 2); > > + /* Size must be a constant which is <= UNITS_PER_WORD and > > + <= the string length. */ > > + if (TREE_CODE (size) != INTEGER_CST || integer_zerop (size)) > > + break; > > + > > + if (!tree_fits_uhwi_p (size)) > > + break; > > + > > + unsigned HOST_WIDE_INT sz = tree_to_uhwi (size); > > + if (sz > UNITS_PER_WORD || sz >= slen) > > + break; > > + > > + tree ch = gimple_call_arg (stmt2, 1); > > + location_t loc = gimple_location (stmt2); > > + if (!useless_type_conversion_p (char_type_node, > > + TREE_TYPE (ch))) > > + ch = fold_convert_loc (loc, char_type_node, ch); > > + const char *p = TREE_STRING_POINTER (TREE_OPERAND (ptr, 0)); > > + unsigned int isize = sz; > > + tree *op = new tree[isize]; > > minor nit - sorry for not spotting earlier. Please use > > tree *op = XALLOCAVEC (tree, isize); > > Ok with that change. > Richard. Fixed. This is the patch I am checking in. Thanks. > > + for (unsigned int i = 0; i < isize; i++) > > + { > > + op[i] = build_int_cst (char_type_node, p[i]); > > + op[i] = fold_build2_loc (loc, EQ_EXPR, boolean_type_node, > > + op[i], ch); > > + } > > + for (unsigned int i = isize - 1; i >= 1; i--) > > + op[i - 1] = fold_convert_loc (loc, boolean_type_node, > > + fold_build2_loc (loc, > > + BIT_IOR_EXPR, > > + boolean_type_node, > > + op[i - 1], > > + op[i])); > > + res = fold_convert_loc (loc, TREE_TYPE (res), op[0]); > > + gimplify_and_update_call_from_tree (gsi_p, res); > > + delete[] op; > > + return true; > > + } > > + break; > > + > > case BUILT_IN_MEMSET: > > if (gimple_call_num_args (stmt2) != 3 > > || gimple_call_lhs (stmt2) > > diff --git a/gcc/tree-ssa-strlen.cc b/gcc/tree-ssa-strlen.cc > > index 7b3e3899ea2..5afbae1b72e 100644 > > --- a/gcc/tree-ssa-strlen.cc > > +++ b/gcc/tree-ssa-strlen.cc > > @@ -3913,8 +3913,8 @@ strlen_pass::handle_builtin_memset (bool *zero_write) > > nonnull if and only RES is used in such expressions exclusively and > > in none other. */ > > > > -static gimple * > > -use_in_zero_equality (tree res, bool exclusive = true) > > +gimple * > > +use_in_zero_equality (tree res, bool exclusive) > > { > > gimple *first_use = NULL; > > > > diff --git a/gcc/tree-ssa-strlen.h b/gcc/tree-ssa-strlen.h > > index 8d155450db8..fdb4d9d7783 100644 > > --- a/gcc/tree-ssa-strlen.h > > +++ b/gcc/tree-ssa-strlen.h > > @@ -35,6 +35,8 @@ struct c_strlen_data; > > extern void get_range_strlen_dynamic (tree, gimple *, c_strlen_data *, > > pointer_query &); > > > > +extern gimple *use_in_zero_equality (tree, bool = true); > > + > > /* APIs internal to strlen pass. Defined in gimple-ssa-sprintf.cc. */ > > extern bool handle_printf_call (gimple_stmt_iterator *, pointer_query &); > > > > -- > > 2.36.1 > > -- H.J. [-- Attachment #2: 0001-Simplify-memchr-with-small-constant-strings.patch --] [-- Type: text/x-patch, Size: 13425 bytes --] From 01cc3401ba3b6b5ba1a4c26b8b5bf9a38feb92fa Mon Sep 17 00:00:00 2001 From: "H.J. Lu" <hjl.tools@gmail.com> Date: Fri, 17 Jun 2022 07:33:06 -0700 Subject: [PATCH] Simplify memchr with small constant strings When memchr is applied on a constant string of no more than the bytes of a word, simplify memchr by checking each byte in the constant string. int f (int a) { return __builtin_memchr ("AE", a, 2) != 0; } is simplified to int f (int a) { return ((char) a == 'A' || (char) a == 'E') != 0; } gcc/ PR tree-optimization/103798 * tree-ssa-forwprop.cc: Include "tree-ssa-strlen.h". (simplify_builtin_call): Inline memchr with constant strings of no more than the bytes of a word. * tree-ssa-strlen.cc (use_in_zero_equality): Make it global. * tree-ssa-strlen.h (use_in_zero_equality): New. gcc/testsuite/ PR tree-optimization/103798 * c-c++-common/pr103798-1.c: New test. * c-c++-common/pr103798-2.c: Likewise. * c-c++-common/pr103798-3.c: Likewise. * c-c++-common/pr103798-4.c: Likewise. * c-c++-common/pr103798-5.c: Likewise. * c-c++-common/pr103798-6.c: Likewise. * c-c++-common/pr103798-7.c: Likewise. * c-c++-common/pr103798-8.c: Likewise. * c-c++-common/pr103798-9.c: Likewise. * c-c++-common/pr103798-10.c: Likewise. --- gcc/testsuite/c-c++-common/pr103798-1.c | 28 +++++++++ gcc/testsuite/c-c++-common/pr103798-10.c | 10 ++++ gcc/testsuite/c-c++-common/pr103798-2.c | 30 ++++++++++ gcc/testsuite/c-c++-common/pr103798-3.c | 28 +++++++++ gcc/testsuite/c-c++-common/pr103798-4.c | 28 +++++++++ gcc/testsuite/c-c++-common/pr103798-5.c | 26 +++++++++ gcc/testsuite/c-c++-common/pr103798-6.c | 27 +++++++++ gcc/testsuite/c-c++-common/pr103798-7.c | 27 +++++++++ gcc/testsuite/c-c++-common/pr103798-8.c | 27 +++++++++ gcc/testsuite/c-c++-common/pr103798-9.c | 10 ++++ gcc/tree-ssa-forwprop.cc | 72 ++++++++++++++++++++++++ gcc/tree-ssa-strlen.cc | 4 +- gcc/tree-ssa-strlen.h | 2 + 13 files changed, 317 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/c-c++-common/pr103798-1.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-10.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-2.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-3.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-4.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-5.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-6.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-7.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-8.c create mode 100644 gcc/testsuite/c-c++-common/pr103798-9.c diff --git a/gcc/testsuite/c-c++-common/pr103798-1.c b/gcc/testsuite/c-c++-common/pr103798-1.c new file mode 100644 index 00000000000..cd3edf569fc --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-1.c @@ -0,0 +1,28 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ + +__attribute__ ((weak)) +int +f (char a) +{ + return __builtin_memchr ("a", a, 1) == 0; +} + +__attribute__ ((weak)) +int +g (char a) +{ + return a != 'a'; +} + +int +main () +{ + for (int i = 0; i < 255; i++) + if (f (i) != g (i)) + __builtin_abort (); + + return 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-10.c b/gcc/testsuite/c-c++-common/pr103798-10.c new file mode 100644 index 00000000000..4677e9539fa --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-10.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-options "-Os -fdump-tree-optimized -save-temps" } */ + +int +f (char a) +{ + return __builtin_memchr ("ac", a, 1) == 0; +} + +/* { dg-final { scan-assembler "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-2.c b/gcc/testsuite/c-c++-common/pr103798-2.c new file mode 100644 index 00000000000..e7e99c3679e --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-2.c @@ -0,0 +1,30 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ + +#include <string.h> + +__attribute__ ((weak)) +int +f (int a) +{ + return memchr ("aE", a, 2) != NULL; +} + +__attribute__ ((weak)) +int +g (char a) +{ + return a == 'a' || a == 'E'; +} + +int +main () +{ + for (int i = 0; i < 255; i++) + if (f (i + 256) != g (i + 256)) + __builtin_abort (); + + return 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-3.c b/gcc/testsuite/c-c++-common/pr103798-3.c new file mode 100644 index 00000000000..ddcedc7e238 --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-3.c @@ -0,0 +1,28 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ + +__attribute__ ((weak)) +int +f (char a) +{ + return __builtin_memchr ("aEgZ", a, 3) == 0; +} + +__attribute__ ((weak)) +int +g (char a) +{ + return a != 'a' && a != 'E' && a != 'g'; +} + +int +main () +{ + for (int i = 0; i < 255; i++) + if (f (i) != g (i)) + __builtin_abort (); + + return 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-4.c b/gcc/testsuite/c-c++-common/pr103798-4.c new file mode 100644 index 00000000000..00e8302a833 --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-4.c @@ -0,0 +1,28 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ + +__attribute__ ((weak)) +int +f (char a) +{ + return __builtin_memchr ("aEgi", a, 4) != 0; +} + +__attribute__ ((weak)) +int +g (char a) +{ + return a == 'a' || a == 'E' || a == 'g' || a == 'i'; +} + +int +main () +{ + for (int i = 0; i < 255; i++) + if (f (i) != g (i)) + __builtin_abort (); + + return 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-5.c b/gcc/testsuite/c-c++-common/pr103798-5.c new file mode 100644 index 00000000000..0d6487a13df --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-5.c @@ -0,0 +1,26 @@ +/* { dg-do run { target int128 } } */ +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ + +__attribute__ ((weak)) +int f(char a) +{ + return __builtin_memchr ("aEgiH", a, 5) == 0; +} + +__attribute__ ((weak)) +int g(char a) +{ + return a != 'a' && a != 'E' && a != 'g' && a != 'i' && a != 'H'; +} + +int +main () +{ + for (int i = 0; i < 255; i++) + if (f (i) != g (i)) + __builtin_abort (); + + return 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-6.c b/gcc/testsuite/c-c++-common/pr103798-6.c new file mode 100644 index 00000000000..5ccb5ee66e0 --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-6.c @@ -0,0 +1,27 @@ +/* { dg-do run { target int128 } } */ +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ + +__attribute__ ((weak)) +int f(char a) +{ + return __builtin_memchr ("aEgiHx", a, 6) != 0; +} + +__attribute__ ((weak)) +int g(char a) +{ + return (a == 'a' || a == 'E' || a == 'g' || a == 'i' || a == 'H' + || a == 'x'); +} + +int +main () +{ + for (int i = 0; i < 255; i++) + if (f (i) != g (i)) + __builtin_abort (); + + return 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-7.c b/gcc/testsuite/c-c++-common/pr103798-7.c new file mode 100644 index 00000000000..40fd38257d1 --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-7.c @@ -0,0 +1,27 @@ +/* { dg-do run { target int128 } } */ +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ + +__attribute__ ((weak)) +int f(char a) +{ + return __builtin_memchr ("aEgiHjZ", a, 7) == 0; +} + +__attribute__ ((weak)) +int g(char a) +{ + return (a != 'a' && a != 'E' && a != 'g' && a != 'i' && a != 'H' + && a != 'j' && a != 'Z'); +} + +int +main () +{ + for (int i = 0; i < 255; i++) + if (f (i) != g (i)) + __builtin_abort (); + + return 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-8.c b/gcc/testsuite/c-c++-common/pr103798-8.c new file mode 100644 index 00000000000..0841b18cea4 --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-8.c @@ -0,0 +1,27 @@ +/* { dg-do run { target int128 } } */ +/* { dg-options "-O2 -fdump-tree-optimized -save-temps" } */ + +__attribute__ ((weak)) +int f(int a) +{ + return __builtin_memchr ("aEgiHx19ABC", a, 8) != 0; +} + +__attribute__ ((weak)) +int g(char a) +{ + return (a == 'a' || a == 'E' || a == 'g' || a == 'i' || a == 'H' + || a == 'x' || a == '1' || a == '9'); +} + +int +main () +{ + for (int i = 0; i < 255; i++) + if (f (i + 256) != g (i + 256)) + __builtin_abort (); + + return 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/testsuite/c-c++-common/pr103798-9.c b/gcc/testsuite/c-c++-common/pr103798-9.c new file mode 100644 index 00000000000..c5f0f94a4b5 --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr103798-9.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-options "-Os -fdump-tree-optimized -save-temps" } */ + +int +f (char a) +{ + return __builtin_memchr ("a", a, 1) == 0; +} + +/* { dg-final { scan-assembler-not "memchr" } } */ diff --git a/gcc/tree-ssa-forwprop.cc b/gcc/tree-ssa-forwprop.cc index 69567ab3275..fdc4bc8909d 100644 --- a/gcc/tree-ssa-forwprop.cc +++ b/gcc/tree-ssa-forwprop.cc @@ -42,6 +42,7 @@ along with GCC; see the file COPYING3. If not see #include "tree-dfa.h" #include "tree-ssa-propagate.h" #include "tree-ssa-dom.h" +#include "tree-ssa-strlen.h" #include "builtins.h" #include "tree-cfgcleanup.h" #include "cfganal.h" @@ -1177,6 +1178,15 @@ constant_pointer_difference (tree p1, tree p2) memcpy (p, "abcd ", 7); call if the latter can be stored by pieces during expansion. + Optimize + memchr ("abcd", a, 4) == 0; + or + memchr ("abcd", a, 4) != 0; + to + (a == 'a' || a == 'b' || a == 'c' || a == 'd') == 0 + or + (a == 'a' || a == 'b' || a == 'c' || a == 'd') != 0 + Also canonicalize __atomic_fetch_op (p, x, y) op x to __atomic_op_fetch (p, x, y) or __atomic_op_fetch (p, x, y) iop x @@ -1193,8 +1203,70 @@ simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2) return false; stmt1 = SSA_NAME_DEF_STMT (vuse); + tree res; + switch (DECL_FUNCTION_CODE (callee2)) { + case BUILT_IN_MEMCHR: + if (gimple_call_num_args (stmt2) == 3 + && (res = gimple_call_lhs (stmt2)) != nullptr + && use_in_zero_equality (res) != nullptr + && CHAR_BIT == 8 + && BITS_PER_UNIT == 8) + { + tree ptr = gimple_call_arg (stmt2, 0); + if (TREE_CODE (ptr) != ADDR_EXPR + || TREE_CODE (TREE_OPERAND (ptr, 0)) != STRING_CST) + break; + unsigned HOST_WIDE_INT slen + = TREE_STRING_LENGTH (TREE_OPERAND (ptr, 0)); + /* It must be a non-empty string constant. */ + if (slen < 2) + break; + /* For -Os, only simplify strings with a single character. */ + if (!optimize_bb_for_speed_p (gimple_bb (stmt2)) + && slen > 2) + break; + tree size = gimple_call_arg (stmt2, 2); + /* Size must be a constant which is <= UNITS_PER_WORD and + <= the string length. */ + if (TREE_CODE (size) != INTEGER_CST || integer_zerop (size)) + break; + + if (!tree_fits_uhwi_p (size)) + break; + + unsigned HOST_WIDE_INT sz = tree_to_uhwi (size); + if (sz > UNITS_PER_WORD || sz >= slen) + break; + + tree ch = gimple_call_arg (stmt2, 1); + location_t loc = gimple_location (stmt2); + if (!useless_type_conversion_p (char_type_node, + TREE_TYPE (ch))) + ch = fold_convert_loc (loc, char_type_node, ch); + const char *p = TREE_STRING_POINTER (TREE_OPERAND (ptr, 0)); + unsigned int isize = sz; + tree *op = XALLOCAVEC (tree, isize); + for (unsigned int i = 0; i < isize; i++) + { + op[i] = build_int_cst (char_type_node, p[i]); + op[i] = fold_build2_loc (loc, EQ_EXPR, boolean_type_node, + op[i], ch); + } + for (unsigned int i = isize - 1; i >= 1; i--) + op[i - 1] = fold_convert_loc (loc, boolean_type_node, + fold_build2_loc (loc, + BIT_IOR_EXPR, + boolean_type_node, + op[i - 1], + op[i])); + res = fold_convert_loc (loc, TREE_TYPE (res), op[0]); + gimplify_and_update_call_from_tree (gsi_p, res); + return true; + } + break; + case BUILT_IN_MEMSET: if (gimple_call_num_args (stmt2) != 3 || gimple_call_lhs (stmt2) diff --git a/gcc/tree-ssa-strlen.cc b/gcc/tree-ssa-strlen.cc index 7b3e3899ea2..5afbae1b72e 100644 --- a/gcc/tree-ssa-strlen.cc +++ b/gcc/tree-ssa-strlen.cc @@ -3913,8 +3913,8 @@ strlen_pass::handle_builtin_memset (bool *zero_write) nonnull if and only RES is used in such expressions exclusively and in none other. */ -static gimple * -use_in_zero_equality (tree res, bool exclusive = true) +gimple * +use_in_zero_equality (tree res, bool exclusive) { gimple *first_use = NULL; diff --git a/gcc/tree-ssa-strlen.h b/gcc/tree-ssa-strlen.h index 8d155450db8..fdb4d9d7783 100644 --- a/gcc/tree-ssa-strlen.h +++ b/gcc/tree-ssa-strlen.h @@ -35,6 +35,8 @@ struct c_strlen_data; extern void get_range_strlen_dynamic (tree, gimple *, c_strlen_data *, pointer_query &); +extern gimple *use_in_zero_equality (tree, bool = true); + /* APIs internal to strlen pass. Defined in gimple-ssa-sprintf.cc. */ extern bool handle_printf_call (gimple_stmt_iterator *, pointer_query &); -- 2.36.1 ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3] Simplify memchr with small constant strings 2022-07-13 16:50 [PATCH v3] Simplify memchr with small constant strings H.J. Lu 2022-07-14 6:42 ` Richard Biener @ 2022-09-07 10:57 ` Jan-Benedict Glaw 2022-09-07 12:00 ` Richard Biener 1 sibling, 1 reply; 6+ messages in thread From: Jan-Benedict Glaw @ 2022-09-07 10:57 UTC (permalink / raw) To: H.J. Lu; +Cc: gcc-patches [-- Attachment #1: Type: text/plain, Size: 3636 bytes --] Hi! On Wed, 2022-07-13 09:50:14 -0700, H.J. Lu via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > When memchr is applied on a constant string of no more than the bytes of > a word, simplify memchr by checking each byte in the constant string. > > int f (int a) > { > return __builtin_memchr ("AE", a, 2) != 0; > } > > is simplified to > > int f (int a) > { > return ((char) a == 'A' || (char) a == 'E') != 0; > } Seems this caused a regression for --target=avr-elf, pru-elf and rl78-elf: .../gcc/configure --prefix=... --enable-werror-always --enable-languages=all --disable-gcov --disable-shared --disable-threads --target=pru-elf --without-headers [...] make V=1 all-gcc [...] /usr/lib/gcc-snapshot/bin/g++ -fno-PIE -c -g -O2 -DIN_GCC -DCROSS_DIRECTORY_STRUCTURE -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror -fno-common -DHAVE_CONFIG_H -I. -I. -I../../gcc/gcc -I../../gcc/gcc/. -I../../gcc/gcc/../include -I../../gcc/gcc/../libcpp/include -I../../gcc/gcc/../libcody -I../../gcc/gcc/../libdecnumber -I../../gcc/gcc/../libdecnumber/dpd -I../libdecnumber -I../../gcc/gcc/../libbacktrace -o tree-ssa-forwprop.o -MT tree-ssa-forwprop.o -MMD -MP -MF ./.deps/tree-ssa-forwprop.TPo ../../gcc/gcc/tree-ssa-forwprop.cc ../../gcc/gcc/tree-ssa-forwprop.cc: In function 'bool simplify_builtin_call(gimple_stmt_iterator*, tree)': ../../gcc/gcc/tree-ssa-forwprop.cc:1258:42: error: array subscript 1 is outside array bounds of 'tree_node* [1]' [-Werror=array-bounds] 1258 | op[i - 1] = fold_convert_loc (loc, boolean_type_node, | ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~ 1259 | fold_build2_loc (loc, | ~~~~~~~~~~~~~~~~~~~~~ 1260 | BIT_IOR_EXPR, | ~~~~~~~~~~~~~ 1261 | boolean_type_node, | ~~~~~~~~~~~~~~~~~~ 1262 | op[i - 1], | ~~~~~~~~~~ 1263 | op[i])); | ~~~~~~~ In file included from ../../gcc/gcc/system.h:707, from ../../gcc/gcc/tree-ssa-forwprop.cc:21: ../../gcc/gcc/../include/libiberty.h:733:36: note: at offset 8 into object of size [0, 8] allocated by '__builtin_alloca' 733 | # define alloca(x) __builtin_alloca(x) | ~~~~~~~~~~~~~~~~^~~ ../../gcc/gcc/../include/libiberty.h:365:40: note: in expansion of macro 'alloca' 365 | #define XALLOCAVEC(T, N) ((T *) alloca (sizeof (T) * (N))) | ^~~~~~ ../../gcc/gcc/tree-ssa-forwprop.cc:1250:22: note: in expansion of macro 'XALLOCAVEC' 1250 | tree *op = XALLOCAVEC (tree, isize); | ^~~~~~~~~~ cc1plus: all warnings being treated as errors make[1]: *** [Makefile:1146: tree-ssa-forwprop.o] Error 1 make[1]: Leaving directory '/var/lib/laminar/run/gcc-pru-elf/1/toolchain-build/gcc' make: *** [Makefile:4583: all-gcc] Error 2 Thanks, Jan-Benedict -- [-- Attachment #2: signature.asc --] [-- Type: application/pgp-signature, Size: 195 bytes --] ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3] Simplify memchr with small constant strings 2022-09-07 10:57 ` Jan-Benedict Glaw @ 2022-09-07 12:00 ` Richard Biener 2022-09-10 5:38 ` Jan-Benedict Glaw 0 siblings, 1 reply; 6+ messages in thread From: Richard Biener @ 2022-09-07 12:00 UTC (permalink / raw) To: Jan-Benedict Glaw; +Cc: H.J. Lu, GCC Patches On Wed, Sep 7, 2022 at 12:58 PM Jan-Benedict Glaw <jbglaw@lug-owl.de> wrote: > > Hi! > > On Wed, 2022-07-13 09:50:14 -0700, H.J. Lu via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > When memchr is applied on a constant string of no more than the bytes of > > a word, simplify memchr by checking each byte in the constant string. > > > > int f (int a) > > { > > return __builtin_memchr ("AE", a, 2) != 0; > > } > > > > is simplified to > > > > int f (int a) > > { > > return ((char) a == 'A' || (char) a == 'E') != 0; > > } > > Seems this caused a regression for --target=avr-elf, pru-elf and > rl78-elf: > > .../gcc/configure --prefix=... --enable-werror-always --enable-languages=all --disable-gcov --disable-shared --disable-threads --target=pru-elf --without-headers > [...] > make V=1 all-gcc > [...] > /usr/lib/gcc-snapshot/bin/g++ -fno-PIE -c -g -O2 -DIN_GCC -DCROSS_DIRECTORY_STRUCTURE -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror -fno-common -DHAVE_CONFIG_H -I. -I. -I../../gcc/gcc -I../../gcc/gcc/. -I../../gcc/gcc/../include -I../../gcc/gcc/../libcpp/include -I../../gcc/gcc/../libcody -I../../gcc/gcc/../libdecnumber -I../../gcc/gcc/../libdecnumber/dpd -I../libdecnumber -I../../gcc/gcc/../libbacktrace -o tree-ssa-forwprop.o -MT tree-ssa-forwprop.o -MMD -MP -MF ./.deps/tree-ssa-forwprop.TPo ../../gcc/gcc/tree-ssa-forwprop.cc > ../../gcc/gcc/tree-ssa-forwprop.cc: In function 'bool simplify_builtin_call(gimple_stmt_iterator*, tree)': > ../../gcc/gcc/tree-ssa-forwprop.cc:1258:42: error: array subscript 1 is outside array bounds of 'tree_node* [1]' [-Werror=array-bounds] > 1258 | op[i - 1] = fold_convert_loc (loc, boolean_type_node, > | ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~ > 1259 | fold_build2_loc (loc, > | ~~~~~~~~~~~~~~~~~~~~~ > 1260 | BIT_IOR_EXPR, > | ~~~~~~~~~~~~~ > 1261 | boolean_type_node, > | ~~~~~~~~~~~~~~~~~~ > 1262 | op[i - 1], > | ~~~~~~~~~~ > 1263 | op[i])); > | ~~~~~~~ > In file included from ../../gcc/gcc/system.h:707, > from ../../gcc/gcc/tree-ssa-forwprop.cc:21: > ../../gcc/gcc/../include/libiberty.h:733:36: note: at offset 8 into object of size [0, 8] allocated by '__builtin_alloca' > 733 | # define alloca(x) __builtin_alloca(x) > | ~~~~~~~~~~~~~~~~^~~ > ../../gcc/gcc/../include/libiberty.h:365:40: note: in expansion of macro 'alloca' > 365 | #define XALLOCAVEC(T, N) ((T *) alloca (sizeof (T) * (N))) > | ^~~~~~ > ../../gcc/gcc/tree-ssa-forwprop.cc:1250:22: note: in expansion of macro 'XALLOCAVEC' > 1250 | tree *op = XALLOCAVEC (tree, isize); > | ^~~~~~~~~~ > cc1plus: all warnings being treated as errors > make[1]: *** [Makefile:1146: tree-ssa-forwprop.o] Error 1 > make[1]: Leaving directory '/var/lib/laminar/run/gcc-pru-elf/1/toolchain-build/gcc' > make: *** [Makefile:4583: all-gcc] Error 2 can you open a bugreport please? > Thanks, > Jan-Benedict > > -- ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3] Simplify memchr with small constant strings 2022-09-07 12:00 ` Richard Biener @ 2022-09-10 5:38 ` Jan-Benedict Glaw 0 siblings, 0 replies; 6+ messages in thread From: Jan-Benedict Glaw @ 2022-09-10 5:38 UTC (permalink / raw) To: Richard Biener; +Cc: H.J. Lu, GCC Patches [-- Attachment #1: Type: text/plain, Size: 2500 bytes --] Hi! On Wed, 2022-09-07 14:00:25 +0200, Richard Biener <richard.guenther@gmail.com> wrote: > On Wed, Sep 7, 2022 at 12:58 PM Jan-Benedict Glaw <jbglaw@lug-owl.de> wrote: > > ../../gcc/gcc/tree-ssa-forwprop.cc:1258:42: error: array subscript 1 is outside array bounds of 'tree_node* [1]' [-Werror=array-bounds] > > 1258 | op[i - 1] = fold_convert_loc (loc, boolean_type_node, > > | ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~ > > 1259 | fold_build2_loc (loc, > > | ~~~~~~~~~~~~~~~~~~~~~ > > 1260 | BIT_IOR_EXPR, > > | ~~~~~~~~~~~~~ > > 1261 | boolean_type_node, > > | ~~~~~~~~~~~~~~~~~~ > > 1262 | op[i - 1], > > | ~~~~~~~~~~ > > 1263 | op[i])); > > | ~~~~~~~ > > In file included from ../../gcc/gcc/system.h:707, > > from ../../gcc/gcc/tree-ssa-forwprop.cc:21: > > ../../gcc/gcc/../include/libiberty.h:733:36: note: at offset 8 into object of size [0, 8] allocated by '__builtin_alloca' > > 733 | # define alloca(x) __builtin_alloca(x) > > | ~~~~~~~~~~~~~~~~^~~ > > ../../gcc/gcc/../include/libiberty.h:365:40: note: in expansion of macro 'alloca' > > 365 | #define XALLOCAVEC(T, N) ((T *) alloca (sizeof (T) * (N))) > > | ^~~~~~ > > ../../gcc/gcc/tree-ssa-forwprop.cc:1250:22: note: in expansion of macro 'XALLOCAVEC' > > 1250 | tree *op = XALLOCAVEC (tree, isize); > > | ^~~~~~~~~~ > > cc1plus: all warnings being treated as errors > > make[1]: *** [Makefile:1146: tree-ssa-forwprop.o] Error 1 > > make[1]: Leaving directory '/var/lib/laminar/run/gcc-pru-elf/1/toolchain-build/gcc' > > make: *** [Makefile:4583: all-gcc] Error 2 > > can you open a bugreport please? Just opened (after re-verification) as https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106900 Thanks, Jan-Benedict -- [-- Attachment #2: signature.asc --] [-- Type: application/pgp-signature, Size: 195 bytes --] ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-09-10 5:38 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-07-13 16:50 [PATCH v3] Simplify memchr with small constant strings H.J. Lu 2022-07-14 6:42 ` Richard Biener 2022-07-14 21:09 ` H.J. Lu 2022-09-07 10:57 ` Jan-Benedict Glaw 2022-09-07 12:00 ` Richard Biener 2022-09-10 5:38 ` Jan-Benedict Glaw
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