diff options
| author | Florian Weimer <fweimer@redhat.com> | 2023-01-02 16:18:02 +0100 |
|---|---|---|
| committer | Florian Weimer <fweimer@redhat.com> | 2023-01-02 16:18:02 +0100 |
| commit | 97bbdb726aba76ead550e25061029cf0aa78671b (patch) | |
| tree | 03ebd3c211a0c1a51ac08db65a25a9285dfb516a /gcc | |
| parent | 3b6cac2b44b384cd2091eaeaebeb3478c253a25d (diff) | |
| download | gcc-97bbdb726aba76ead550e25061029cf0aa78671b.zip gcc-97bbdb726aba76ead550e25061029cf0aa78671b.tar.gz gcc-97bbdb726aba76ead550e25061029cf0aa78671b.tar.bz2 | |
Define __LIBGCC_DWARF_REG_SIZES_CONSTANT__ if DWARF register size is constant
And use that to speed up the libgcc unwinder.
gcc/
* debug.h (dwarf_reg_sizes_constant): Declare.
* dwarf2cfi.cc (dwarf_reg_sizes_constant): New function.
gcc/c-family/
* c-cppbuiltin.cc (__LIBGCC_DWARF_REG_SIZES_CONSTANT__):
Define if constant is known.
libgcc/
* unwind-dw2.c (dwarf_reg_size): New function.
(_Unwind_GetGR, _Unwind_SetGR, _Unwind_SetGRPtr)
(_Unwind_SetSpColumn, uw_install_context_1): Use it.
(uw_init_context_1): Do not initialize dwarf_reg_size_table
if not in use.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/c-family/c-cppbuiltin.cc | 6 | ||||
| -rw-r--r-- | gcc/debug.h | 2 | ||||
| -rw-r--r-- | gcc/dwarf2cfi.cc | 23 |
3 files changed, 31 insertions, 0 deletions
diff --git a/gcc/c-family/c-cppbuiltin.cc b/gcc/c-family/c-cppbuiltin.cc index 333f3e1..011478c 100644 --- a/gcc/c-family/c-cppbuiltin.cc +++ b/gcc/c-family/c-cppbuiltin.cc @@ -1521,6 +1521,12 @@ c_cpp_builtins (cpp_reader *pfile) #endif builtin_define_with_int_value ("__LIBGCC_DWARF_FRAME_REGISTERS__", DWARF_FRAME_REGISTERS); + { + int value = dwarf_reg_sizes_constant (); + if (value > 0) + builtin_define_with_int_value ("__LIBGCC_DWARF_REG_SIZES_CONSTANT__", + value); + } #ifdef EH_RETURN_STACKADJ_RTX cpp_define (pfile, "__LIBGCC_EH_RETURN_STACKADJ_RTX__"); #endif diff --git a/gcc/debug.h b/gcc/debug.h index 799d5e3..4fe9f35 100644 --- a/gcc/debug.h +++ b/gcc/debug.h @@ -245,6 +245,8 @@ extern const struct gcc_debug_hooks vmsdbg_debug_hooks; /* Dwarf2 frame information. */ +extern int dwarf_reg_sizes_constant (); + extern void dwarf2out_begin_prologue (unsigned int, unsigned int, const char *); extern void dwarf2out_vms_end_prologue (unsigned int, const char *); diff --git a/gcc/dwarf2cfi.cc b/gcc/dwarf2cfi.cc index 4d2bd86..d5a27dc 100644 --- a/gcc/dwarf2cfi.cc +++ b/gcc/dwarf2cfi.cc @@ -334,6 +334,29 @@ generate_dwarf_reg_sizes (poly_uint16 *sizes) targetm.init_dwarf_reg_sizes_extra (sizes); } +/* Return 0 if the DWARF register sizes are not constant, otherwise + return the size constant. */ + +int +dwarf_reg_sizes_constant () +{ + poly_uint16 *sizes = XALLOCAVEC (poly_uint16, DWARF_FRAME_REGISTERS); + generate_dwarf_reg_sizes (sizes); + + int result; + for (unsigned int i = 0; i < DWARF_FRAME_REGISTERS; i++) + { + unsigned short value; + if (!sizes[i].is_constant (&value)) + return 0; + if (i == 0) + result = value; + else if (result != value) + return 0; + } + return result; +} + /* Generate code to initialize the dwarf register size table located at the provided ADDRESS. */ |