From 3ab9b88e2ac91062b6d493fe32bd101a55006c6a Mon Sep 17 00:00:00 2001 From: Manjunath Matti Date: Tue, 19 Mar 2024 15:29:48 -0500 Subject: powerpc: Add HWCAP3/HWCAP4 data to TCB for Power Architecture. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch adds a new feature for powerpc. In order to get faster access to the HWCAP3/HWCAP4 masks, similar to HWCAP/HWCAP2 (i.e. for implementing __builtin_cpu_supports() in GCC) without the overhead of reading them from the auxiliary vector, we now reserve space for them in the TCB. This is an ABI change for GLIBC 2.39. Suggested-by: Peter Bergner Reviewed-by: Peter Bergner --- sysdeps/powerpc/dl-procinfo.h | 52 ++++++++++++++++++++++++++++++------------- 1 file changed, 37 insertions(+), 15 deletions(-) (limited to 'sysdeps/powerpc/dl-procinfo.h') diff --git a/sysdeps/powerpc/dl-procinfo.h b/sysdeps/powerpc/dl-procinfo.h index 68f4241095..f8cb343877 100644 --- a/sysdeps/powerpc/dl-procinfo.h +++ b/sysdeps/powerpc/dl-procinfo.h @@ -22,16 +22,17 @@ #include #include /* This defines the PPC_FEATURE[2]_* macros. */ -/* The total number of available bits (including those prior to - _DL_HWCAP_FIRST). Some of these bits might not be used. */ -#define _DL_HWCAP_COUNT 64 +/* Feature masks are all 32-bits in size. */ +#define _DL_HWCAP_SIZE 32 -/* Features started at bit 31 and decremented as new features were added. */ -#define _DL_HWCAP_LAST 31 +/* AT_HWCAP2 feature strings follow the AT_HWCAP feature strings. */ +#define _DL_HWCAP2_OFFSET _DL_HWCAP_SIZE -/* AT_HWCAP2 features started at bit 31 and decremented as new features were - added. HWCAP2 feature bits start at bit 0. */ -#define _DL_HWCAP2_LAST 31 +/* AT_HWCAP3 feature strings follow the AT_HWCAP2 feature strings. */ +#define _DL_HWCAP3_OFFSET (_DL_HWCAP2_OFFSET + _DL_HWCAP_SIZE) + +/* AT_HWCAP4 feature strings follow the AT_HWCAP3 feature strings. */ +#define _DL_HWCAP4_OFFSET (_DL_HWCAP3_OFFSET + _DL_HWCAP_SIZE) /* These bits influence library search. */ #define HWCAP_IMPORTANT (PPC_FEATURE_HAS_ALTIVEC \ @@ -187,21 +188,42 @@ _dl_procinfo (unsigned int type, unsigned long int word) case AT_HWCAP: _dl_printf ("AT_HWCAP: "); - for (int i = 0; i <= _DL_HWCAP_LAST; ++i) + for (int i = 0; i < _DL_HWCAP_SIZE; ++i) if (word & (1 << i)) _dl_printf (" %s", _dl_hwcap_string (i)); break; case AT_HWCAP2: { - unsigned int offset = _DL_HWCAP_LAST + 1; _dl_printf ("AT_HWCAP2: "); - /* We have to go through them all because the kernel added the - AT_HWCAP2 features starting with the high bits. */ - for (int i = 0; i <= _DL_HWCAP2_LAST; ++i) - if (word & (1 << i)) - _dl_printf (" %s", _dl_hwcap_string (offset + i)); + /* We have to go through them all because the kernel added the + AT_HWCAP2 features starting with the high bits. */ + for (int i = 0; i < _DL_HWCAP_SIZE; ++i) + if (word & (1 << i)) + _dl_printf (" %s", _dl_hwcap_string (_DL_HWCAP2_OFFSET + i)); + break; + } + case AT_HWCAP3: + { + _dl_printf ("AT_HWCAP3: "); + + /* We have to go through them all because the kernel added the + AT_HWCAP3 features starting with the high bits. */ + for (int i = 0; i < _DL_HWCAP_SIZE; ++i) + if (word & (1 << i)) + _dl_printf (" %s", _dl_hwcap_string (_DL_HWCAP3_OFFSET + i)); + break; + } + case AT_HWCAP4: + { + _dl_printf ("AT_HWCAP4: "); + + /* We have to go through them all because the kernel added the + AT_HWCAP4 features starting with the high bits. */ + for (int i = 0; i <= _DL_HWCAP_SIZE; ++i) + if (word & (1 << i)) + _dl_printf (" %s", _dl_hwcap_string (_DL_HWCAP4_OFFSET + i)); break; } case AT_L1I_CACHEGEOMETRY: -- cgit 1.4.1