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libiberty: support digits in cpp mangled clone names

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Currently libiberty fails to demangle the name of cloned functions if
the clone-type-identifier contains numbers.

This can be observed with the following example:

    $ cat > ex.cc <<EOT
    void foo (float *, float *)
      __attribute__((target_clones("avx2,avx,sse4.1,default")));

    void foo (float *, float *) {}
    EOT
    $ gcc -c ex.cc
    $ nm -C ex.o | grep foo
    0000000000000000 i foo(float*, float*)
    0000000000000026 t foo(float*, float*) [clone .avx.1]
    0000000000000013 t _Z3fooPfS_.avx2.0
    0000000000000000 t foo(float*, float*) [clone .default.3]
    0000000000000000 W foo(float*, float*) [clone .resolver]
    0000000000000039 t _Z3fooPfS_.sse4_1.2

In this example, gcc creates clones for the FOO function, each matching
one of the specified targets.  When inspecting the binary, nm (and other
libiberty-based tools, including gdb) fails to demangle the symbol names
if the clone identifier contains numbers.

Form my understanding of the mangling convention[1], clone names are
part of vendor-specific suffixes and do not have rule preventing them
from containing digits.

This commit proposes to fix the demangling.  With this commit (ported to
binutils), nm gives the following output:

    $ nm-new -C ex.o | grep foo
    0000000000000000 i foo(float*, float*)
    0000000000000026 t foo(float*, float*) [clone .avx.1]
    0000000000000013 t foo(float*, float*) [clone .avx2.0]
    0000000000000000 t foo(float*, float*) [clone .default.3]
    0000000000000000 W foo(float*, float*) [clone .resolver]
    0000000000000039 t foo(float*, float*) [clone .sse4_1.2]

Tested on x86_86-linux with 'make check-libiberty'.

[1] https://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangling

libiberty/ChangeLog:

	* cp-demangle.c (d_clone_suffix): Support digits in clone tag
	names.
	* testsuite/demangle-expected: Check demangling of clone symbols
	with digits in name.
This commit is contained in:
Lancelot SIX 2021-12-30 11:36:52 -05:00 • committed by Jeff Law
parent 52441f18db
commit be674bdd11
2 changed files with 8 additions and 2 deletions
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5
libiberty/cp-demangle.c
View file

@ -3884,10 +3884,11 @@ d_clone_suffix (struct d_info *di, struct demangle_component *encoding)
const char *pend = suffix;
struct demangle_component *n;
if (*pend == '.' && (IS_LOWER (pend[1]) || pend[1] == '_'))
if (*pend == '.' && (IS_LOWER (pend[1]) || IS_DIGIT (pend[1])
|| pend[1] == '_'))
{
pend += 2;
while (IS_LOWER (*pend) || *pend == '_')
while (IS_LOWER (*pend) || IS_DIGIT (*pend) || *pend == '_')
++pend;
}
while (*pend == '.' && IS_DIGIT (pend[1]))

5
libiberty/testsuite/demangle-expected
View file

@ -1164,6 +1164,11 @@ foo(int) [clone ._omp_cpyfn.6]
foo
#
--format=gnu-v3 --no-params
_Z3fooPfS_S_j.sse4_1.2
foo(float*, float*, float*, unsigned int) [clone .sse4_1.2]
foo
#
--format=gnu-v3 --no-params
_Z1fIKFvvES0_Evv
void f<void () const, void () const>()
f<void () const, void () const>