| Message ID | 20220705162715.133539-1-hjl.tools@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v3] Enable __memcmpeq after seeing __memcmpeq prototype | expand |
On Tue, Jul 5, 2022 at 6:27 PM H.J. Lu <hjl.tools@gmail.com> wrote: > > extern int __memcmpeq (const void *, const void *, size_t); > > was was added to GLIBC 2.35. Expand BUILT_IN_MEMCMP_EQ to __memcmpeq > after seeing __memcmpeq prototype > > gcc/ > > * builtins.cc (expand_builtin): Issue an error for > BUILT_IN___MEMCMPEQ if there is no __memcmpeq prototype. Expand > BUILT_IN_MEMCMP_EQ to BUILT_IN___MEMCMP_EQ if there is __memcmpeq > prototype. > * builtins.def (BUILT_IN___MEMCMPEQ): New. > > gcc/testsuite/ > > * c-c++-common/memcmpeq-1.c: New test. > * c-c++-common/memcmpeq-2.c: Likewise. > * c-c++-common/memcmpeq-3.c: Likewise. > * c-c++-common/memcmpeq-4.c: Likewise. > * c-c++-common/memcmpeq-5.c: Likewise. > * c-c++-common/memcmpeq-6.c: Likewise. > * c-c++-common/memcmpeq.h: Likewise. > --- > gcc/builtins.cc | 14 +++++++++++++- > gcc/builtins.def | 3 +++ > gcc/testsuite/c-c++-common/memcmpeq-1.c | 11 +++++++++++ > gcc/testsuite/c-c++-common/memcmpeq-2.c | 11 +++++++++++ > gcc/testsuite/c-c++-common/memcmpeq-3.c | 11 +++++++++++ > gcc/testsuite/c-c++-common/memcmpeq-4.c | 11 +++++++++++ > gcc/testsuite/c-c++-common/memcmpeq-5.c | 11 +++++++++++ > gcc/testsuite/c-c++-common/memcmpeq-6.c | 10 ++++++++++ > gcc/testsuite/c-c++-common/memcmpeq.h | 11 +++++++++++ > 9 files changed, 92 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/c-c++-common/memcmpeq-1.c > create mode 100644 gcc/testsuite/c-c++-common/memcmpeq-2.c > create mode 100644 gcc/testsuite/c-c++-common/memcmpeq-3.c > create mode 100644 gcc/testsuite/c-c++-common/memcmpeq-4.c > create mode 100644 gcc/testsuite/c-c++-common/memcmpeq-5.c > create mode 100644 gcc/testsuite/c-c++-common/memcmpeq-6.c > create mode 100644 gcc/testsuite/c-c++-common/memcmpeq.h > > diff --git a/gcc/builtins.cc b/gcc/builtins.cc > index e6816d5c865..2254a597bec 100644 > --- a/gcc/builtins.cc > +++ b/gcc/builtins.cc > @@ -7395,6 +7395,15 @@ expand_builtin (tree exp, rtx target, rtx subtarget, machine_mode mode, > return target; > break; > > + case BUILT_IN___MEMCMPEQ: > + if (!builtin_decl_declared_p (BUILT_IN___MEMCMPEQ)) > + { > + error ("use of %<__builtin___memcmpeq ()%> without " > + "%<__memcmpeq%> prototype"); > + return const0_rtx; > + } > + break; > + I think we don't need this - if the user manually calls __builtin__memcmpeq () he should know what he does. > /* Expand it as BUILT_IN_MEMCMP_EQ first. If not successful, change it > back to a BUILT_IN_STRCMP. Remember to delete the 3rd parameter > when changing it to a strcmp call. */ > @@ -7448,7 +7457,10 @@ expand_builtin (tree exp, rtx target, rtx subtarget, machine_mode mode, > return target; > if (fcode == BUILT_IN_MEMCMP_EQ) > { > - tree newdecl = builtin_decl_explicit (BUILT_IN_MEMCMP); > + tree newdecl = builtin_decl_explicit > + (builtin_decl_declared_p (BUILT_IN___MEMCMPEQ) > + ? BUILT_IN___MEMCMPEQ > + : BUILT_IN_MEMCMP); > TREE_OPERAND (exp, 1) = build_fold_addr_expr (newdecl); > } > break; > diff --git a/gcc/builtins.def b/gcc/builtins.def > index 005976f34e9..95642c6acdf 100644 > --- a/gcc/builtins.def > +++ b/gcc/builtins.def > @@ -965,6 +965,9 @@ DEF_BUILTIN_STUB (BUILT_IN_ALLOCA_WITH_ALIGN_AND_MAX, "__builtin_alloca_with_ali > equality with zero. */ > DEF_BUILTIN_STUB (BUILT_IN_MEMCMP_EQ, "__builtin_memcmp_eq") > > +/* Similar to BUILT_IN_MEMCMP_EQ, but is mapped to __memcmpeq. */ > +DEF_EXT_LIB_BUILTIN (BUILT_IN___MEMCMPEQ, "__memcmpeq", BT_FN_INT_CONST_PTR_CONST_PTR_SIZE, ATTR_PURE_NOTHROW_NONNULL_LEAF) > + it would be nice to not make __builtin___memcmpeq or __memcmpeq available to the user without a __memcmpeq declaration. I'm not sure this can be arranged for. In principle we're just assigning an optional libfunc name to BUILT_IN_MEMCMP_EQ when __memcmpeq is available. Joseph, is there any convenient mechanism available I am missing? Otherwise the builtin should probably be documented (as well as the behavior wrt a __memcmpeq declaration). Thanks, Richard. > /* An internal version of strcmp/strncmp, used when the result is only > tested for equality with zero. */ > DEF_BUILTIN_STUB (BUILT_IN_STRCMP_EQ, "__builtin_strcmp_eq") > diff --git a/gcc/testsuite/c-c++-common/memcmpeq-1.c b/gcc/testsuite/c-c++-common/memcmpeq-1.c > new file mode 100644 > index 00000000000..14622f0d765 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/memcmpeq-1.c > @@ -0,0 +1,11 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2" } */ > +/* { dg-final { scan-assembler "__memcmpeq" } } */ > + > +#include "memcmpeq.h" > + > +int > +foo (const char *s1, const char *s2, size_t len) > +{ > + return __builtin_memcmp (s1, s2, len) != 0; > +} > diff --git a/gcc/testsuite/c-c++-common/memcmpeq-2.c b/gcc/testsuite/c-c++-common/memcmpeq-2.c > new file mode 100644 > index 00000000000..f57f279f173 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/memcmpeq-2.c > @@ -0,0 +1,11 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2" } */ > +/* { dg-final { scan-assembler "__memcmpeq" } } */ > + > +#include "memcmpeq.h" > + > +int > +foo (const char *s1, const char *s2, size_t len) > +{ > + return memcmp (s1, s2, len) == 0; > +} > diff --git a/gcc/testsuite/c-c++-common/memcmpeq-3.c b/gcc/testsuite/c-c++-common/memcmpeq-3.c > new file mode 100644 > index 00000000000..2ca2131c23a > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/memcmpeq-3.c > @@ -0,0 +1,11 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2" } */ > +/* { dg-final { scan-assembler-not "__memcmpeq" } } */ > + > +#include "memcmpeq.h" > + > +int > +foo (const char *s1, const char *s2, size_t len) > +{ > + return memcmp (s1, s2, len); > +} > diff --git a/gcc/testsuite/c-c++-common/memcmpeq-4.c b/gcc/testsuite/c-c++-common/memcmpeq-4.c > new file mode 100644 > index 00000000000..d59765894e7 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/memcmpeq-4.c > @@ -0,0 +1,11 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2" } */ > +/* { dg-final { scan-assembler-not "__memcmpeq" } } */ > + > +#include <stddef.h> > + > +int > +foo (const char *s1, const char *s2, size_t len) > +{ > + return __builtin_memcmp_eq (s1, s2, len) != 0; > +} > diff --git a/gcc/testsuite/c-c++-common/memcmpeq-5.c b/gcc/testsuite/c-c++-common/memcmpeq-5.c > new file mode 100644 > index 00000000000..cb12358cd87 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/memcmpeq-5.c > @@ -0,0 +1,11 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2" } */ > +/* { dg-final { scan-assembler "__memcmpeq" } } */ > + > +#include "memcmpeq.h" > + > +int > +foo (const char *s1, const char *s2, size_t len) > +{ > + return __builtin___memcmpeq (s1, s2, len) != 0; > +} > diff --git a/gcc/testsuite/c-c++-common/memcmpeq-6.c b/gcc/testsuite/c-c++-common/memcmpeq-6.c > new file mode 100644 > index 00000000000..8f983c05a44 > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/memcmpeq-6.c > @@ -0,0 +1,10 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2" } */ > + > +#include <stddef.h> > + > +int > +foo (const char *s1, const char *s2, size_t len) > +{ > + return __builtin___memcmpeq (s1, s2, len) != 0; /* { dg-error "__builtin___memcmpeq" } */ > +} > diff --git a/gcc/testsuite/c-c++-common/memcmpeq.h b/gcc/testsuite/c-c++-common/memcmpeq.h > new file mode 100644 > index 00000000000..3f731a4806b > --- /dev/null > +++ b/gcc/testsuite/c-c++-common/memcmpeq.h > @@ -0,0 +1,11 @@ > +#include <string.h> > + > +#if __cplusplus > +extern "C" { > +#endif > + > +extern int __memcmpeq (const void *, const void *, size_t); > + > +#if __cplusplus > +} > +#endif > -- > 2.36.1 >
diff --git a/gcc/builtins.cc b/gcc/builtins.cc index e6816d5c865..2254a597bec 100644 --- a/gcc/builtins.cc +++ b/gcc/builtins.cc @@ -7395,6 +7395,15 @@ expand_builtin (tree exp, rtx target, rtx subtarget, machine_mode mode, return target; break; + case BUILT_IN___MEMCMPEQ: + if (!builtin_decl_declared_p (BUILT_IN___MEMCMPEQ)) + { + error ("use of %<__builtin___memcmpeq ()%> without " + "%<__memcmpeq%> prototype"); + return const0_rtx; + } + break; + /* Expand it as BUILT_IN_MEMCMP_EQ first. If not successful, change it back to a BUILT_IN_STRCMP. Remember to delete the 3rd parameter when changing it to a strcmp call. */ @@ -7448,7 +7457,10 @@ expand_builtin (tree exp, rtx target, rtx subtarget, machine_mode mode, return target; if (fcode == BUILT_IN_MEMCMP_EQ) { - tree newdecl = builtin_decl_explicit (BUILT_IN_MEMCMP); + tree newdecl = builtin_decl_explicit + (builtin_decl_declared_p (BUILT_IN___MEMCMPEQ) + ? BUILT_IN___MEMCMPEQ + : BUILT_IN_MEMCMP); TREE_OPERAND (exp, 1) = build_fold_addr_expr (newdecl); } break; diff --git a/gcc/builtins.def b/gcc/builtins.def index 005976f34e9..95642c6acdf 100644 --- a/gcc/builtins.def +++ b/gcc/builtins.def @@ -965,6 +965,9 @@ DEF_BUILTIN_STUB (BUILT_IN_ALLOCA_WITH_ALIGN_AND_MAX, "__builtin_alloca_with_ali equality with zero. */ DEF_BUILTIN_STUB (BUILT_IN_MEMCMP_EQ, "__builtin_memcmp_eq") +/* Similar to BUILT_IN_MEMCMP_EQ, but is mapped to __memcmpeq. */ +DEF_EXT_LIB_BUILTIN (BUILT_IN___MEMCMPEQ, "__memcmpeq", BT_FN_INT_CONST_PTR_CONST_PTR_SIZE, ATTR_PURE_NOTHROW_NONNULL_LEAF) + /* An internal version of strcmp/strncmp, used when the result is only tested for equality with zero. */ DEF_BUILTIN_STUB (BUILT_IN_STRCMP_EQ, "__builtin_strcmp_eq") diff --git a/gcc/testsuite/c-c++-common/memcmpeq-1.c b/gcc/testsuite/c-c++-common/memcmpeq-1.c new file mode 100644 index 00000000000..14622f0d765 --- /dev/null +++ b/gcc/testsuite/c-c++-common/memcmpeq-1.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* { dg-final { scan-assembler "__memcmpeq" } } */ + +#include "memcmpeq.h" + +int +foo (const char *s1, const char *s2, size_t len) +{ + return __builtin_memcmp (s1, s2, len) != 0; +} diff --git a/gcc/testsuite/c-c++-common/memcmpeq-2.c b/gcc/testsuite/c-c++-common/memcmpeq-2.c new file mode 100644 index 00000000000..f57f279f173 --- /dev/null +++ b/gcc/testsuite/c-c++-common/memcmpeq-2.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* { dg-final { scan-assembler "__memcmpeq" } } */ + +#include "memcmpeq.h" + +int +foo (const char *s1, const char *s2, size_t len) +{ + return memcmp (s1, s2, len) == 0; +} diff --git a/gcc/testsuite/c-c++-common/memcmpeq-3.c b/gcc/testsuite/c-c++-common/memcmpeq-3.c new file mode 100644 index 00000000000..2ca2131c23a --- /dev/null +++ b/gcc/testsuite/c-c++-common/memcmpeq-3.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* { dg-final { scan-assembler-not "__memcmpeq" } } */ + +#include "memcmpeq.h" + +int +foo (const char *s1, const char *s2, size_t len) +{ + return memcmp (s1, s2, len); +} diff --git a/gcc/testsuite/c-c++-common/memcmpeq-4.c b/gcc/testsuite/c-c++-common/memcmpeq-4.c new file mode 100644 index 00000000000..d59765894e7 --- /dev/null +++ b/gcc/testsuite/c-c++-common/memcmpeq-4.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* { dg-final { scan-assembler-not "__memcmpeq" } } */ + +#include <stddef.h> + +int +foo (const char *s1, const char *s2, size_t len) +{ + return __builtin_memcmp_eq (s1, s2, len) != 0; +} diff --git a/gcc/testsuite/c-c++-common/memcmpeq-5.c b/gcc/testsuite/c-c++-common/memcmpeq-5.c new file mode 100644 index 00000000000..cb12358cd87 --- /dev/null +++ b/gcc/testsuite/c-c++-common/memcmpeq-5.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* { dg-final { scan-assembler "__memcmpeq" } } */ + +#include "memcmpeq.h" + +int +foo (const char *s1, const char *s2, size_t len) +{ + return __builtin___memcmpeq (s1, s2, len) != 0; +} diff --git a/gcc/testsuite/c-c++-common/memcmpeq-6.c b/gcc/testsuite/c-c++-common/memcmpeq-6.c new file mode 100644 index 00000000000..8f983c05a44 --- /dev/null +++ b/gcc/testsuite/c-c++-common/memcmpeq-6.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ + +#include <stddef.h> + +int +foo (const char *s1, const char *s2, size_t len) +{ + return __builtin___memcmpeq (s1, s2, len) != 0; /* { dg-error "__builtin___memcmpeq" } */ +} diff --git a/gcc/testsuite/c-c++-common/memcmpeq.h b/gcc/testsuite/c-c++-common/memcmpeq.h new file mode 100644 index 00000000000..3f731a4806b --- /dev/null +++ b/gcc/testsuite/c-c++-common/memcmpeq.h @@ -0,0 +1,11 @@ +#include <string.h> + +#if __cplusplus +extern "C" { +#endif + +extern int __memcmpeq (const void *, const void *, size_t); + +#if __cplusplus +} +#endif