From: Lancelot SIX <lsix@lancelotsix.com>
Date: Thu, 30 Dec 2021 16:36:52 +0000 (-0500)
Subject: libiberty: support digits in cpp mangled clone names
X-Git-Tag: basepoints/gcc-13~2159
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=be674bdd11d5fa6b20d469e6d6f43c26da9e744f;p=thirdparty%2Fgcc.git

libiberty: support digits in cpp mangled clone names

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.
---

diff --git a/libiberty/cp-demangle.c b/libiberty/cp-demangle.c
index 33490f602854..fb576cb4c974 100644
--- a/libiberty/cp-demangle.c
+++ b/libiberty/cp-demangle.c
@@ -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]))
diff --git a/libiberty/testsuite/demangle-expected b/libiberty/testsuite/demangle-expected
index 19a0d621bc01..de54ad73cc8e 100644
--- a/libiberty/testsuite/demangle-expected
+++ b/libiberty/testsuite/demangle-expected
@@ -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>