[PATCH 1/1] tools: ftdgrep: use /* fallthrough */ as needed
GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled. Let's use it consistently.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de --- tools/fdtgrep.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/tools/fdtgrep.c b/tools/fdtgrep.c index 7e168a1e6b..8b4d2765ad 100644 --- a/tools/fdtgrep.c +++ b/tools/fdtgrep.c @@ -923,7 +923,9 @@ static const char usage_synopsis[] = /* Helper for getopt case statements */ #define case_USAGE_COMMON_FLAGS \ case 'h': usage(NULL); \ + /* fallthrough */ \ case 'V': util_version(); \ + /* fallthrough */ \ case '?': usage("unknown option");
static const char usage_short_opts[] = @@ -1085,6 +1087,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[])
switch (opt) { case_USAGE_COMMON_FLAGS + /* fallthrough */ case 'a': disp->show_addr = 1; break; @@ -1096,7 +1099,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[]) break; case 'C': inc = 0; - /* no break */ + /* fallthrough */ case 'c': type = FDT_IS_COMPAT; break; @@ -1111,7 +1114,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[]) break; case 'G': inc = 0; - /* no break */ + /* fallthrough */ case 'g': type = FDT_ANY_GLOBAL; break; @@ -1129,7 +1132,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[]) break; case 'N': inc = 0; - /* no break */ + /* fallthrough */ case 'n': type = FDT_IS_NODE; break; @@ -1148,7 +1151,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[]) break; case 'P': inc = 0; - /* no break */ + /* fallthrough */ case 'p': type = FDT_IS_PROP; break; -- 2.26.2
On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote:
GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled.
FYI.
Linux decided to not use /* fallthrough */ any more because Clang does not recognize it.
__attribute__((__fallthrough__)) is supported by both Clang and recent GCC.
Linux is now doing treewide conversion from /* fallthrough */ to 'fallthrough;'.
See include/linux/compiler_attributes.h in Linux.
I do not know if U-Boot wants to align with it. (up to Tom ?)
Let's use it consistently.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de
tools/fdtgrep.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/tools/fdtgrep.c b/tools/fdtgrep.c index 7e168a1e6b..8b4d2765ad 100644 --- a/tools/fdtgrep.c +++ b/tools/fdtgrep.c @@ -923,7 +923,9 @@ static const char usage_synopsis[] = /* Helper for getopt case statements */ #define case_USAGE_COMMON_FLAGS \ case 'h': usage(NULL); \
/* fallthrough */ \ case 'V': util_version(); \/* fallthrough */ \ case '?': usage("unknown option");static const char usage_short_opts[] = @@ -1085,6 +1087,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[])
switch (opt) { case_USAGE_COMMON_FLAGS
/* fallthrough */ case 'a': disp->show_addr = 1; break;@@ -1096,7 +1099,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[]) break; case 'C': inc = 0;
/* no break */
/* fallthrough */ case 'c': type = FDT_IS_COMPAT; break;@@ -1111,7 +1114,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[]) break; case 'G': inc = 0;
/* no break */
/* fallthrough */ case 'g': type = FDT_ANY_GLOBAL; break;@@ -1129,7 +1132,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[]) break; case 'N': inc = 0;
/* no break */
/* fallthrough */ case 'n': type = FDT_IS_NODE; break;@@ -1148,7 +1151,7 @@ static void scan_args(struct display_info *disp, int argc, char *argv[]) break; case 'P': inc = 0;
/* no break */
/* fallthrough */ case 'p': type = FDT_IS_PROP; break;-- 2.26.2
On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote:
On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote:
GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled.
FYI.
Linux decided to not use /* fallthrough */ any more because Clang does not recognize it.
__attribute__((__fallthrough__)) is supported by both Clang and recent GCC.
Linux is now doing treewide conversion from /* fallthrough */ to 'fallthrough;'.
See include/linux/compiler_attributes.h in Linux.
I do not know if U-Boot wants to align with it. (up to Tom ?)
A re-sync on the compiler headers again and making use of this sounds like a good idea, yes.
On 5/11/20 8:40 PM, Tom Rini wrote:
On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote:
On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote:
GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled.
FYI.
Linux decided to not use /* fallthrough */ any more because Clang does not recognize it.
__attribute__((__fallthrough__)) is supported by both Clang and recent GCC.
In fact Linux has a define:
include/linux/compiler_attributes.h:200:# define fallthrough __attribute__((__fallthrough__))
And in the code you would use
case foo: fallthrough; case bar:
But the Linux kernel still has a lot of lines with
/* fallthrough */
Documentation/process/deprecated.rst:
<cite> As there have been a long list of flaws `due to missing "break" statements https://cwe.mitre.org/data/definitions/484.html`_, we no longer allow implicit fall-through. In order to identify intentional fall-through cases, we have adopted a pseudo-keyword macro "fallthrough" which expands to gcc's extension `__attribute__((__fallthrough__)) https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html`_. (When the C17/C18 `[[fallthrough]]` syntax is more commonly supported by C compilers, static analyzers, and IDEs, we can switch to using that syntax for the macro pseudo-keyword.) </cite>
Using the attribute is not standard C and not any better than using the comment. The real target is the C17 syntax.
Linux is now doing treewide conversion from /* fallthrough */ to 'fallthrough;'.
See include/linux/compiler_attributes.h in Linux.
I do not know if U-Boot wants to align with it. (up to Tom ?)
A re-sync on the compiler headers again and making use of this sounds like a good idea, yes.
We should enable -Wimplicit-fallthrough like the kernel does. This defaults to -Wimplicit-fallthrough=3 and is happy with both the comment as well as with the attribute.
@Tom: Will you update the compiler headers within this release cycle? Otherwise we should take the patch as is to get us closer to the -Wimplicit-fallthrough target.
Best regards
Heinrich
On Mon, May 11, 2020 at 09:08:03PM +0200, Heinrich Schuchardt wrote:
On 5/11/20 8:40 PM, Tom Rini wrote:
On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote:
On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote:
GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled.
FYI.
Linux decided to not use /* fallthrough */ any more because Clang does not recognize it.
__attribute__((__fallthrough__)) is supported by both Clang and recent GCC.
In fact Linux has a define:
include/linux/compiler_attributes.h:200:# define fallthrough __attribute__((__fallthrough__))
And in the code you would use
case foo: fallthrough; case bar:
But the Linux kernel still has a lot of lines with
/* fallthrough */
Documentation/process/deprecated.rst:
<cite> As there have been a long list of flaws `due to missing "break" statements <https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow implicit fall-through. In order to identify intentional fall-through cases, we have adopted a pseudo-keyword macro "fallthrough" which expands to gcc's extension `__attribute__((__fallthrough__)) <https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_. (When the C17/C18 `[[fallthrough]]` syntax is more commonly supported by C compilers, static analyzers, and IDEs, we can switch to using that syntax for the macro pseudo-keyword.) </cite>
Using the attribute is not standard C and not any better than using the comment. The real target is the C17 syntax.
Linux is now doing treewide conversion from /* fallthrough */ to 'fallthrough;'.
See include/linux/compiler_attributes.h in Linux.
I do not know if U-Boot wants to align with it. (up to Tom ?)
A re-sync on the compiler headers again and making use of this sounds like a good idea, yes.
We should enable -Wimplicit-fallthrough like the kernel does. This defaults to -Wimplicit-fallthrough=3 and is happy with both the comment as well as with the attribute.
@Tom: Will you update the compiler headers within this release cycle? Otherwise we should take the patch as is to get us closer to the -Wimplicit-fallthrough target.
I'm not going to update it for this release cycle. I've done the initial import and build and there's some fairly large changes related to inlining that I want to look at harder to see if we can/should do something about (I don't want to derail this thread, I'll start another). But it's very far from zero size change and given the inline changes I think it'll need real testing.
And since the kernel isn't making a huge use yet of fallthrough; we can afford to look a little harder at things.
On Tue, May 12, 2020 at 11:04:38PM -0400, Tom Rini wrote:
On Mon, May 11, 2020 at 09:08:03PM +0200, Heinrich Schuchardt wrote:
On 5/11/20 8:40 PM, Tom Rini wrote:
On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote:
On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote:
GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled.
FYI.
Linux decided to not use /* fallthrough */ any more because Clang does not recognize it.
__attribute__((__fallthrough__)) is supported by both Clang and recent GCC.
In fact Linux has a define:
include/linux/compiler_attributes.h:200:# define fallthrough __attribute__((__fallthrough__))
And in the code you would use
case foo: fallthrough; case bar:
But the Linux kernel still has a lot of lines with
/* fallthrough */
Documentation/process/deprecated.rst:
<cite> As there have been a long list of flaws `due to missing "break" statements <https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow implicit fall-through. In order to identify intentional fall-through cases, we have adopted a pseudo-keyword macro "fallthrough" which expands to gcc's extension `__attribute__((__fallthrough__)) <https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_. (When the C17/C18 `[[fallthrough]]` syntax is more commonly supported by C compilers, static analyzers, and IDEs, we can switch to using that syntax for the macro pseudo-keyword.) </cite>
Using the attribute is not standard C and not any better than using the comment. The real target is the C17 syntax.
Linux is now doing treewide conversion from /* fallthrough */ to 'fallthrough;'.
See include/linux/compiler_attributes.h in Linux.
I do not know if U-Boot wants to align with it. (up to Tom ?)
A re-sync on the compiler headers again and making use of this sounds like a good idea, yes.
We should enable -Wimplicit-fallthrough like the kernel does. This defaults to -Wimplicit-fallthrough=3 and is happy with both the comment as well as with the attribute.
@Tom: Will you update the compiler headers within this release cycle? Otherwise we should take the patch as is to get us closer to the -Wimplicit-fallthrough target.
I'm not going to update it for this release cycle. I've done the initial import and build and there's some fairly large changes related to inlining that I want to look at harder to see if we can/should do something about (I don't want to derail this thread, I'll start another). But it's very far from zero size change and given the inline changes I think it'll need real testing.
And since the kernel isn't making a huge use yet of fallthrough; we can afford to look a little harder at things.
I think I've figured out the inline issue which is that we need scripts/Kconfig.include from the kernel, CC_HAS_ASM_INLINE Kconfig option, and re-sync with Kconfiglib, but that's still going to be enough stuff that I don't think it's good to pull in at -rc2.
Hi Tom,
On Wed, May 13, 2020 at 11:42 PM Tom Rini trini@konsulko.com wrote:
On Tue, May 12, 2020 at 11:04:38PM -0400, Tom Rini wrote:
On Mon, May 11, 2020 at 09:08:03PM +0200, Heinrich Schuchardt wrote:
On 5/11/20 8:40 PM, Tom Rini wrote:
On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote:
On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote:
GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled.
FYI.
Linux decided to not use /* fallthrough */ any more because Clang does not recognize it.
__attribute__((__fallthrough__)) is supported by both Clang and recent GCC.
In fact Linux has a define:
include/linux/compiler_attributes.h:200:# define fallthrough __attribute__((__fallthrough__))
And in the code you would use
case foo: fallthrough; case bar:But the Linux kernel still has a lot of lines with
/* fallthrough */
Documentation/process/deprecated.rst:
<cite> As there have been a long list of flaws `due to missing "break" statements <https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow implicit fall-through. In order to identify intentional fall-through cases, we have adopted a pseudo-keyword macro "fallthrough" which expands to gcc's extension `__attribute__((__fallthrough__)) <https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_. (When the C17/C18 `[[fallthrough]]` syntax is more commonly supported by C compilers, static analyzers, and IDEs, we can switch to using that syntax for the macro pseudo-keyword.) </cite>
Using the attribute is not standard C and not any better than using the comment. The real target is the C17 syntax.
Linux is now doing treewide conversion from /* fallthrough */ to 'fallthrough;'.
See include/linux/compiler_attributes.h in Linux.
I do not know if U-Boot wants to align with it. (up to Tom ?)
A re-sync on the compiler headers again and making use of this sounds like a good idea, yes.
We should enable -Wimplicit-fallthrough like the kernel does. This defaults to -Wimplicit-fallthrough=3 and is happy with both the comment as well as with the attribute.
@Tom: Will you update the compiler headers within this release cycle? Otherwise we should take the patch as is to get us closer to the -Wimplicit-fallthrough target.
I'm not going to update it for this release cycle. I've done the initial import and build and there's some fairly large changes related to inlining that I want to look at harder to see if we can/should do something about (I don't want to derail this thread, I'll start another). But it's very far from zero size change and given the inline changes I think it'll need real testing.
And since the kernel isn't making a huge use yet of fallthrough; we can afford to look a little harder at things.
I think I've figured out the inline issue which is that we need scripts/Kconfig.include from the kernel, CC_HAS_ASM_INLINE Kconfig option, and re-sync with Kconfiglib, but that's still going to be enough stuff that I don't think it's good to pull in at -rc2.
I do not get how 'asm inline' support is related to this topic.
GCC 9 started to support 'asm inline' for the better inlining heuristic. The kernel uses a bunch of inline assembly that is not as expensive as it looks.
As GCC is agnostic about the real cost of inline assembly, 'asm inline' is a good hint if people know the real cost is quite small. Then, GCC will be able to inline more functions.
I do not know how important it is for U-Boot, though.
What is causing you a trouble?
-- Best Regards Masahiro Yamada
On Thu, May 14, 2020 at 01:05:37AM +0900, Masahiro Yamada wrote:
Hi Tom,
On Wed, May 13, 2020 at 11:42 PM Tom Rini trini@konsulko.com wrote:
On Tue, May 12, 2020 at 11:04:38PM -0400, Tom Rini wrote:
On Mon, May 11, 2020 at 09:08:03PM +0200, Heinrich Schuchardt wrote:
On 5/11/20 8:40 PM, Tom Rini wrote:
On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote:
On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote: > > GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled.
FYI.
Linux decided to not use /* fallthrough */ any more because Clang does not recognize it.
__attribute__((__fallthrough__)) is supported by both Clang and recent GCC.
In fact Linux has a define:
include/linux/compiler_attributes.h:200:# define fallthrough __attribute__((__fallthrough__))
And in the code you would use
case foo: fallthrough; case bar:But the Linux kernel still has a lot of lines with
/* fallthrough */
Documentation/process/deprecated.rst:
<cite> As there have been a long list of flaws `due to missing "break" statements <https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow implicit fall-through. In order to identify intentional fall-through cases, we have adopted a pseudo-keyword macro "fallthrough" which expands to gcc's extension `__attribute__((__fallthrough__)) <https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_. (When the C17/C18 `[[fallthrough]]` syntax is more commonly supported by C compilers, static analyzers, and IDEs, we can switch to using that syntax for the macro pseudo-keyword.) </cite>
Using the attribute is not standard C and not any better than using the comment. The real target is the C17 syntax.
Linux is now doing treewide conversion from /* fallthrough */ to 'fallthrough;'.
See include/linux/compiler_attributes.h in Linux.
I do not know if U-Boot wants to align with it. (up to Tom ?)
A re-sync on the compiler headers again and making use of this sounds like a good idea, yes.
We should enable -Wimplicit-fallthrough like the kernel does. This defaults to -Wimplicit-fallthrough=3 and is happy with both the comment as well as with the attribute.
@Tom: Will you update the compiler headers within this release cycle? Otherwise we should take the patch as is to get us closer to the -Wimplicit-fallthrough target.
I'm not going to update it for this release cycle. I've done the initial import and build and there's some fairly large changes related to inlining that I want to look at harder to see if we can/should do something about (I don't want to derail this thread, I'll start another). But it's very far from zero size change and given the inline changes I think it'll need real testing.
And since the kernel isn't making a huge use yet of fallthrough; we can afford to look a little harder at things.
I think I've figured out the inline issue which is that we need scripts/Kconfig.include from the kernel, CC_HAS_ASM_INLINE Kconfig option, and re-sync with Kconfiglib, but that's still going to be enough stuff that I don't think it's good to pull in at -rc2.
I do not get how 'asm inline' support is related to this topic.
GCC 9 started to support 'asm inline' for the better inlining heuristic. The kernel uses a bunch of inline assembly that is not as expensive as it looks.
As GCC is agnostic about the real cost of inline assembly, 'asm inline' is a good hint if people know the real cost is quite small. Then, GCC will be able to inline more functions.
I do not know how important it is for U-Boot, though.
What is causing you a trouble?
So, it turns out that while we do want to grab the changes so that we can have CC_HAS_ASM_INLINE via Kconfig, it's not "it". What I see for virtually every board (with gcc-9.3 from kernel.org) is something like: rock960-rk3399 : all -8 rodata -4 spl/u-boot-spl:all +992 spl/u-boot-spl:text +992 text -4 u-boot: add: 67/-9, grow: 74/-92 bytes: 5072/-4928 (144) function old new delta static._compare_and_overwrite_entry - 348 +348 menu_interactive_choice - 288 +288 hex2bin - 200 +200 __fswab64 - 176 +176 __fswab32 - 144 +144 sdhci_reset - 136 +136 dwmci_fifo_ready - 124 +124 fdt_offset_ptr_ - 120 +120 menu_items_iter - 108 +108 generic_fls - 100 +100 fdt_set_totalsize - 96 +96 static.generic_fls - 84 +84 clk_get_by_indexed_prop - 80 +80 fdt_read_number - 76 +76 do_fdt 3984 4060 +76 usb_kbd_poll_for_event - 72 +72 rpc_lookup_req - 72 +72 menu_item_key_match - 72 +72 bin2hex - 68 +68 asix_get_phy_addr - 68 +68 fdt_setprop_u64 - 64 +64 fdt_set_size_dt_strings - 64 +64 fdt_set_off_dt_strings - 64 +64 zalloc - 60 +60 static.strlcat - 60 +60 dwmci_wait_reset - 60 +60 menu_item_print - 56 +56 is_zero_ethaddr - 56 +56 asix_eth_start 228 284 +56 set_sctlr - 52 +52 menu_item_destroy - 52 +52 get_sctlr - 48 +48 fdt_setprop_u32 - 48 +48 is_valid_ethaddr - 44 +44 is_hex_prefix - 44 +44 fdt_data_size_ - 44 +44 list_del - 40 +40 fdt_mem_rsv_ - 40 +40 dev_read_u32_default - 40 +40 __tolower - 40 +40 le32_to_int - 36 +36 fdt_open_into 392 428 +36 _debug_uart_putc - 36 +36 usb_gadget_disconnect - 32 +32 usb_gadget_connect - 32 +32 fdt_set_size_dt_struct - 32 +32 fdt_set_off_dt_struct - 32 +32 fdt_packblocks_ 176 208 +32 fdt_blocks_misordered_ 96 128 +32 __get_unaligned_le32 - 32 +32 fdtdec_get_number 48 76 +28 fdt_ro_probe_ 128 156 +28 env_flags_validate 632 660 +28 clk_valid - 28 +28 clk_set_rate 52 80 +28 clk_set_parent 52 80 +28 clk_get_rate 52 80 +28 clk_free 44 72 +28 clk_enable 52 80 +28 clk_disable 52 80 +28 bootstage_error - 28 +28 asix_set_sw_mii - 28 +28 asix_set_hw_mii - 28 +28 uuid_str_to_bin 396 420 +24 ofnode_read_u64 92 116 +24 fdt_mem_rsv 60 84 +24 fdt_get_property_namelen 44 68 +24 static.usb_ep_queue - 20 +20 static.image_get_size - 20 +20 is_extended - 20 +20 flush_dcache_all - 20 +20 fdt_splice_mem_rsv_ 96 116 +20 fdt_offset_ptr 104 124 +20 fdt_check_header 276 296 +20 eth_validate_ethaddr_str 152 172 +20 android_image_get_kcomp 84 104 +20 usb_ep_free_request - 16 +16 static.image_get_magic - 16 +16 static.image_get_load - 16 +16 nfs_read_req 228 244 +16 malloc_cache_aligned - 16 +16 image_print_contents 448 464 +16 fit_get_end 16 32 +16 fdt_add_property_ 388 404 +16 dwc3_flush_cache - 16 +16 do_bootm_states 2376 2392 +16 dev_read_bool - 16 +16 static.image_get_ep - 12 +12 static.dev_read_u32_default - 12 +12 nfs_readlink_reply 336 348 +12 nfs_read_reply 404 416 +12 fit_image_get_address 132 144 +12 fdtdec_parse_phandle_with_args 336 348 +12 fdt_shrink_to_minimum 220 232 +12 fdt_header_size 12 24 +12 fdt_del_node 96 108 +12 fdt_add_mem_rsv 124 136 +12 boot_get_fdt 1028 1040 +12 android_image_get_kernel 572 584 +12 update_package_list 280 288 +8 nfs_lookup_reply 292 300 +8 net_copy_u32 - 8 +8 net_copy_ip - 8 +8 image_multi_getimg 132 140 +8 image_check_dcrc 68 76 +8 guidcmp - 8 +8 genimg_get_format 92 100 +8 free_packagelist 68 76 +8 fit_image_load 1608 1616 +8 fdt_valid 204 212 +8 fdt_splice_struct_ 96 104 +8 fdt_rw_probe_ 108 116 +8 fdt_num_mem_rsv 60 68 +8 fdt_next_tag 256 264 +8 fdt_getprop_namelen 100 108 +8 dhcp_extended 616 624 +8 boot_get_ramdisk 964 972 +8 xhci_submit_control_msg 2732 2736 +4 static.image_get_hcrc - 4 +4 static.image_get_dcrc - 4 +4 static.__swab32p - 4 +4 sd_get_capabilities 432 436 +4 rpc_req 288 292 +4 rpc_lookup_reply 180 184 +4 print_data 444 448 +4 nfs_umountall_reply 136 140 +4 nfs_readlink_req 192 196 +4 nfs_mount_req 180 184 +4 nfs_mount_reply 148 152 +4 nfs_lookup_req 324 328 +4 image_setup_libfdt 284 288 +4 image_check_hcrc 80 84 +4 fdtdec_get_int_array 96 100 +4 fdt_setprop_placeholder 216 220 +4 fdt_getprop_by_offset 184 188 +4 fdt_get_string 288 292 +4 fdt_get_property_namelen_ 212 216 +4 fdt_get_property_by_offset_ 100 104 +4 fdt_get_phandle 120 124 +4 fdt_get_mem_rsv 108 112 +4 boot_relocate_fdt 424 428 +4 spi_slave_ofdata_to_platdata 432 428 -4 sdhci_send_command 1660 1656 -4 i2c_chip_ofdata_to_platdata 100 96 -4 file_fat_write_at 652 648 -4 fdt_get_name 164 160 -4 fat_size 204 200 -4 fat_opendir 172 168 -4 fat_exists 128 124 -4 efi_search_protocol 148 144 -4 efi_install_multiple_protocol_interfaces 552 548 -4 dwmci_send_cmd 1556 1552 -4 remove_strings_package 124 116 -8 fdt_splice_ 148 140 -8 fdt_pack_reg 216 208 -8 fdt_add_subnode_namelen 284 276 -8 fastboot_start_ep 124 116 -8 efi_signal_event 200 192 -8 efi_process_event_queue 144 136 -8 efi_install_fdt 868 860 -8 efi_install_configuration_table 456 448 -8 efi_disconnect_all_drivers 404 396 -8 clk_set_defaults 516 508 -8 ustrtoull 144 132 -12 ustrtoul 144 132 -12 rx_handler_dl_image 204 192 -12 rx_handler_command 368 356 -12 remove_keyboard_package 76 64 -12 regulator_common_ofdata_to_platdata 188 176 -12 read_bootsectandvi 308 296 -12 free_keyboard_layouts 80 68 -12 file_fat_read_at 864 852 -12 fat_mkdir 928 916 -12 fat_itr_root 444 432 -12 fastboot_tx_write_str 152 140 -12 fastboot_set_alt 316 304 -12 efi_uninstall_protocol_interface 112 100 -12 efi_uninstall_protocol 216 204 -12 efi_uninstall_multiple_protocol_interfaces 464 452 -12 efi_remove_protocol 100 88 -12 efi_locate_handle 380 368 -12 efi_exit_boot_services 336 324 -12 efi_delete_handle 60 48 -12 efi_close_protocol 220 208 -12 dwc3_prepare_trbs 772 760 -12 dwc3_gadget_uboot_handle_interrupt 1552 1540 -12 dwc3_gadget_giveback 240 228 -12 g_dnl_bind 376 360 -16 fastboot_disable 140 124 -16 ext4fs_iterate_dir 656 640 -16 efi_locate_protocol 280 264 -16 efi_add_protocol 320 304 -16 dhcp_process_options 512 496 -16 fat_unlink 668 648 -20 ext4fs_read_inode 392 372 -20 ext4fs_mount 236 216 -20 dhcp_handler 972 952 -20 _parse_integer_fixup_radix 248 228 -20 g_dnl_unbind 52 28 -24 fdt_initrd 436 412 -24 efi_hii_package_len 24 - -24 dcache_status 52 24 -28 usb_kbd_testc 144 112 -32 usb_kbd_getc 116 84 -32 ext4fs_find_file1 660 628 -32 asix_eth_probe 700 668 -32 dwc3_gadget_ep_enable 264 228 -36 printch 80 40 -40 eth_write_hwaddr 220 180 -40 efi_close_event 268 224 -44 asix_mdio_write 140 96 -44 add_packages 928 884 -44 of_bus_default_map 168 120 -48 menu_destroy 128 80 -48 of_bus_default_translate 184 132 -52 mmc_init 2724 2668 -56 static.dwmci_wait_reset 60 - -60 __of_translate_address 624 564 -60 remove_guid_package 64 - -64 menu_item_add 240 176 -64 menu_default_set 148 76 -72 icache_disable 100 24 -76 static.clk_get_by_indexed_prop 80 - -80 dcache_disable 132 48 -84 icache_enable 116 28 -88 nfs_send 260 168 -92 xhci_microframes_to_exponent 104 - -104 skip_num 104 - -104 spi_nor_scan 2196 2088 -108 part_get_info_extended 716 604 -112 static.dwmci_fifo_ready 124 - -124 static.sdhci_reset 136 - -136 print_partition_extended 648 512 -136 asix_mdio_read 140 - -140 static.parse_attr 468 308 -160 efi_set_variable_common 1440 1276 -164 efi_get_variable_common 548 384 -164 eth_post_probe 580 404 -176 dcache_enable 272 44 -228 read_allocated_block 2120 1832 -288 hsearch_r 1080 728 -352 menu_get_choice 480 84 -396 spl-u-boot-spl: add: 23/-5, grow: 25/-12 bytes: 1700/-768 (932) function old new delta sdhci_reset - 136 +136 __fswab64 - 132 +132 dwmci_fifo_ready - 124 +124 fdt_offset_ptr_ - 120 +120 __fswab32 - 104 +104 fdt_mem_rsv_ - 80 +80 clk_get_by_indexed_prop - 80 +80 fdt_set_size_dt_strings - 64 +64 fdt_set_off_dt_strings - 64 +64 dwmci_wait_reset - 60 +60 set_sctlr - 52 +52 get_sctlr - 48 +48 fdt_setprop_u32 - 48 +48 fdt_data_size_ - 44 +44 __tolower - 40 +40 _debug_uart_putc - 36 +36 fdt_set_size_dt_struct - 32 +32 fdt_set_off_dt_struct - 32 +32 fdtdec_get_number 48 76 +28 fdt_offset_ptr 52 80 +28 clk_valid - 28 +28 clk_set_rate 52 80 +28 clk_set_parent 52 80 +28 clk_get_rate 52 80 +28 ofnode_read_u64 92 116 +24 flush_dcache_all - 20 +20 fdt_splice_mem_rsv_ 96 116 +20 fdt_check_header 28 44 +16 dev_read_u32_default - 16 +16 dev_read_bool - 16 +16 fit_image_get_address 132 144 +12 fdtdec_parse_phandle_with_args 336 348 +12 fdt_shrink_to_minimum 220 232 +12 fdt_get_property_by_offset_ 36 48 +12 fdt_add_property_ 340 352 +12 fdt_splice_struct_ 96 104 +8 fdt_get_string 64 72 +8 fdt_add_mem_rsv 112 120 +8 static.__swab32p - 4 +4 sd_get_capabilities 432 436 +4 fdtdec_get_int_array 96 100 +4 fdt_setprop_placeholder 196 200 +4 fdt_num_mem_rsv 64 68 +4 fdt_next_tag 192 196 +4 fdt_getprop_by_offset 80 84 +4 fdt_get_property_namelen_ 200 204 +4 fdt_get_phandle 120 124 +4 fdt_get_mem_rsv 52 56 +4 sdhci_send_command 1660 1656 -4 fdt_del_mem_rsv 104 100 -4 dwmci_send_cmd 1556 1552 -4 fdt_splice_ 148 140 -8 fdt_add_subnode_namelen 260 252 -8 fdt_get_name 68 56 -12 clk_set_defaults 488 472 -16 fdt_mem_rsv 20 - -20 _parse_integer_fixup_radix 248 228 -20 fdt_record_loadable 372 336 -36 printch 80 40 -40 static.dwmci_wait_reset 60 - -60 static.clk_get_by_indexed_prop 80 - -80 dcache_disable 132 48 -84 mmc_init 4576 4464 -112 static.dwmci_fifo_ready 124 - -124 static.sdhci_reset 136 - -136
Which is not good, and I need to dig in to a bit more to see what changes cause this.
On Thu, May 14, 2020 at 1:13 AM Tom Rini trini@konsulko.com wrote:
On Thu, May 14, 2020 at 01:05:37AM +0900, Masahiro Yamada wrote:
Hi Tom,
On Wed, May 13, 2020 at 11:42 PM Tom Rini trini@konsulko.com wrote:
On Tue, May 12, 2020 at 11:04:38PM -0400, Tom Rini wrote:
On Mon, May 11, 2020 at 09:08:03PM +0200, Heinrich Schuchardt wrote:
On 5/11/20 8:40 PM, Tom Rini wrote:
On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote: > On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote: >> >> GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled. > > FYI. > > Linux decided to not use /* fallthrough */ any more > because Clang does not recognize it. > > __attribute__((__fallthrough__)) is supported > by both Clang and recent GCC.
In fact Linux has a define:
include/linux/compiler_attributes.h:200:# define fallthrough __attribute__((__fallthrough__))
And in the code you would use
case foo: fallthrough; case bar:But the Linux kernel still has a lot of lines with
/* fallthrough */
Documentation/process/deprecated.rst:
<cite> As there have been a long list of flaws `due to missing "break" statements <https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow implicit fall-through. In order to identify intentional fall-through cases, we have adopted a pseudo-keyword macro "fallthrough" which expands to gcc's extension `__attribute__((__fallthrough__)) <https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_. (When the C17/C18 `[[fallthrough]]` syntax is more commonly supported by C compilers, static analyzers, and IDEs, we can switch to using that syntax for the macro pseudo-keyword.) </cite>
Using the attribute is not standard C and not any better than using the comment. The real target is the C17 syntax.
> > > Linux is now doing treewide conversion > from /* fallthrough */ to 'fallthrough;'. > > See include/linux/compiler_attributes.h in Linux. > > I do not know if U-Boot wants to align with it. > (up to Tom ?)
A re-sync on the compiler headers again and making use of this sounds like a good idea, yes.
We should enable -Wimplicit-fallthrough like the kernel does. This defaults to -Wimplicit-fallthrough=3 and is happy with both the comment as well as with the attribute.
@Tom: Will you update the compiler headers within this release cycle? Otherwise we should take the patch as is to get us closer to the -Wimplicit-fallthrough target.
I'm not going to update it for this release cycle. I've done the initial import and build and there's some fairly large changes related to inlining that I want to look at harder to see if we can/should do something about (I don't want to derail this thread, I'll start another). But it's very far from zero size change and given the inline changes I think it'll need real testing.
And since the kernel isn't making a huge use yet of fallthrough; we can afford to look a little harder at things.
I think I've figured out the inline issue which is that we need scripts/Kconfig.include from the kernel, CC_HAS_ASM_INLINE Kconfig option, and re-sync with Kconfiglib, but that's still going to be enough stuff that I don't think it's good to pull in at -rc2.
I do not get how 'asm inline' support is related to this topic.
GCC 9 started to support 'asm inline' for the better inlining heuristic. The kernel uses a bunch of inline assembly that is not as expensive as it looks.
As GCC is agnostic about the real cost of inline assembly, 'asm inline' is a good hint if people know the real cost is quite small. Then, GCC will be able to inline more functions.
I do not know how important it is for U-Boot, though.
What is causing you a trouble?
So, it turns out that while we do want to grab the changes so that we can have CC_HAS_ASM_INLINE via Kconfig, it's not "it". What I see for virtually every board (with gcc-9.3 from kernel.org) is something like: rock960-rk3399 : all -8 rodata -4 spl/u-boot-spl:all +992 spl/u-boot-spl:text +992 text -4 u-boot: add: 67/-9, grow: 74/-92 bytes: 5072/-4928 (144) function old new delta static._compare_and_overwrite_entry - 348 +348 menu_interactive_choice - 288 +288 hex2bin - 200 +200 __fswab64 - 176 +176 __fswab32 - 144 +144 sdhci_reset - 136 +136 dwmci_fifo_ready - 124 +124 fdt_offset_ptr_ - 120 +120 menu_items_iter - 108 +108 generic_fls - 100 +100 fdt_set_totalsize - 96 +96 static.generic_fls - 84 +84
OK, these functions previously disappeared because all of the function call-sites were inlined.
If you resync <linux/compier*.h> with latest Linux, they are not necessarily inlined.
In current U-Boot, 'static inline' is actually replaced with __attribute__((always_inline)). So, inlining is forcible.
See the code.
include/linux/compiler-gcc.h
#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4) #define inline inline __attribute__((always_inline)) notrace #define __inline__ __inline__ __attribute__((always_inline)) notrace #define __inline __inline __attribute__((always_inline)) notrace
In Linux, the following commits stopped doing that. (both my commits)
ac7c3e4ff401b304489a031938dbeaab585bfe0a 889b3c1245de48ed0cacf7aebb25c489d3e4a3e9
Now, 'inline' is just a compiler hint. The compiler does the best judge whether to inline the function or not.
-- Best Regards Masahiro Yamada
On Thu, May 14, 2020 at 02:27:20AM +0900, Masahiro Yamada wrote:
On Thu, May 14, 2020 at 1:13 AM Tom Rini trini@konsulko.com wrote:
On Thu, May 14, 2020 at 01:05:37AM +0900, Masahiro Yamada wrote:
Hi Tom,
On Wed, May 13, 2020 at 11:42 PM Tom Rini trini@konsulko.com wrote:
On Tue, May 12, 2020 at 11:04:38PM -0400, Tom Rini wrote:
On Mon, May 11, 2020 at 09:08:03PM +0200, Heinrich Schuchardt wrote:
On 5/11/20 8:40 PM, Tom Rini wrote: > On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote: >> On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote: >>> >>> GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled. >> >> FYI. >> >> Linux decided to not use /* fallthrough */ any more >> because Clang does not recognize it. >> >> __attribute__((__fallthrough__)) is supported >> by both Clang and recent GCC. In fact Linux has a define:
include/linux/compiler_attributes.h:200:# define fallthrough __attribute__((__fallthrough__))
And in the code you would use
case foo: fallthrough; case bar:But the Linux kernel still has a lot of lines with
/* fallthrough */
Documentation/process/deprecated.rst:
<cite> As there have been a long list of flaws `due to missing "break" statements <https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow implicit fall-through. In order to identify intentional fall-through cases, we have adopted a pseudo-keyword macro "fallthrough" which expands to gcc's extension `__attribute__((__fallthrough__)) <https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_. (When the C17/C18 `[[fallthrough]]` syntax is more commonly supported by C compilers, static analyzers, and IDEs, we can switch to using that syntax for the macro pseudo-keyword.) </cite>
Using the attribute is not standard C and not any better than using the comment. The real target is the C17 syntax.
>> >> >> Linux is now doing treewide conversion >> from /* fallthrough */ to 'fallthrough;'. >> >> See include/linux/compiler_attributes.h in Linux. >> >> I do not know if U-Boot wants to align with it. >> (up to Tom ?) > > A re-sync on the compiler headers again and making use of this sounds > like a good idea, yes. >
We should enable -Wimplicit-fallthrough like the kernel does. This defaults to -Wimplicit-fallthrough=3 and is happy with both the comment as well as with the attribute.
@Tom: Will you update the compiler headers within this release cycle? Otherwise we should take the patch as is to get us closer to the -Wimplicit-fallthrough target.
I'm not going to update it for this release cycle. I've done the initial import and build and there's some fairly large changes related to inlining that I want to look at harder to see if we can/should do something about (I don't want to derail this thread, I'll start another). But it's very far from zero size change and given the inline changes I think it'll need real testing.
And since the kernel isn't making a huge use yet of fallthrough; we can afford to look a little harder at things.
I think I've figured out the inline issue which is that we need scripts/Kconfig.include from the kernel, CC_HAS_ASM_INLINE Kconfig option, and re-sync with Kconfiglib, but that's still going to be enough stuff that I don't think it's good to pull in at -rc2.
I do not get how 'asm inline' support is related to this topic.
GCC 9 started to support 'asm inline' for the better inlining heuristic. The kernel uses a bunch of inline assembly that is not as expensive as it looks.
As GCC is agnostic about the real cost of inline assembly, 'asm inline' is a good hint if people know the real cost is quite small. Then, GCC will be able to inline more functions.
I do not know how important it is for U-Boot, though.
What is causing you a trouble?
So, it turns out that while we do want to grab the changes so that we can have CC_HAS_ASM_INLINE via Kconfig, it's not "it". What I see for virtually every board (with gcc-9.3 from kernel.org) is something like: rock960-rk3399 : all -8 rodata -4 spl/u-boot-spl:all +992 spl/u-boot-spl:text +992 text -4 u-boot: add: 67/-9, grow: 74/-92 bytes: 5072/-4928 (144) function old new delta static._compare_and_overwrite_entry - 348 +348 menu_interactive_choice - 288 +288 hex2bin - 200 +200 __fswab64 - 176 +176 __fswab32 - 144 +144 sdhci_reset - 136 +136 dwmci_fifo_ready - 124 +124 fdt_offset_ptr_ - 120 +120 menu_items_iter - 108 +108 generic_fls - 100 +100 fdt_set_totalsize - 96 +96 static.generic_fls - 84 +84
OK, these functions previously disappeared because all of the function call-sites were inlined.
If you resync <linux/compier*.h> with latest Linux, they are not necessarily inlined.
In current U-Boot, 'static inline' is actually replaced with __attribute__((always_inline)). So, inlining is forcible.
See the code.
include/linux/compiler-gcc.h
#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4) #define inline inline __attribute__((always_inline)) notrace #define __inline__ __inline__ __attribute__((always_inline)) notrace #define __inline __inline __attribute__((always_inline)) notrace
In Linux, the following commits stopped doing that. (both my commits)
ac7c3e4ff401b304489a031938dbeaab585bfe0a 889b3c1245de48ed0cacf7aebb25c489d3e4a3e9
Now, 'inline' is just a compiler hint. The compiler does the best judge whether to inline the function or not.
Ah, OK. And the kernel is uninterested in bringing back forcing inlineing for size reasons as it's gone for LTO instead of ffunction-sections/fdata-sections and discarding sections (and we're in turn a ways off from that as we need to move to gcc linking) I assume. Thanks!
On Wed, May 13, 2020 at 02:41:51PM -0400, Tom Rini wrote:
On Thu, May 14, 2020 at 02:27:20AM +0900, Masahiro Yamada wrote:
On Thu, May 14, 2020 at 1:13 AM Tom Rini trini@konsulko.com wrote:
On Thu, May 14, 2020 at 01:05:37AM +0900, Masahiro Yamada wrote:
Hi Tom,
On Wed, May 13, 2020 at 11:42 PM Tom Rini trini@konsulko.com wrote:
On Tue, May 12, 2020 at 11:04:38PM -0400, Tom Rini wrote:
On Mon, May 11, 2020 at 09:08:03PM +0200, Heinrich Schuchardt wrote: > On 5/11/20 8:40 PM, Tom Rini wrote: > > On Sun, May 10, 2020 at 10:12:07PM +0900, Masahiro Yamada wrote: > >> On Sun, May 10, 2020 at 12:12 AM Heinrich Schuchardt xypron.glpk@gmx.de wrote: > >>> > >>> GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled. > >> > >> FYI. > >> > >> Linux decided to not use /* fallthrough */ any more > >> because Clang does not recognize it. > >> > >> __attribute__((__fallthrough__)) is supported > >> by both Clang and recent GCC. > In fact Linux has a define: > > include/linux/compiler_attributes.h:200:# define fallthrough > __attribute__((__fallthrough__)) > > And in the code you would use > > case foo: > fallthrough; > case bar: > > But the Linux kernel still has a lot of lines with > > /* fallthrough */ > > Documentation/process/deprecated.rst: > > <cite> > As there have been a long list of flaws `due to missing "break" > statements https://cwe.mitre.org/data/definitions/484.html`_, we no > longer allow implicit fall-through. In order to identify intentional > fall-through cases, we have adopted a pseudo-keyword macro "fallthrough" > which expands to gcc's extension `__attribute__((__fallthrough__)) > https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html`_. (When > the C17/C18 `[[fallthrough]]` syntax is more commonly supported by C > compilers, static analyzers, and IDEs, we can switch to using that > syntax for the macro pseudo-keyword.) > </cite> > > Using the attribute is not standard C and not any better than using the > comment. The real target is the C17 syntax. > > >> > >> > >> Linux is now doing treewide conversion > >> from /* fallthrough */ to 'fallthrough;'. > >> > >> See include/linux/compiler_attributes.h in Linux. > >> > >> I do not know if U-Boot wants to align with it. > >> (up to Tom ?) > > > > A re-sync on the compiler headers again and making use of this sounds > > like a good idea, yes. > > > > We should enable -Wimplicit-fallthrough like the kernel does. This > defaults to -Wimplicit-fallthrough=3 and is happy with both the comment > as well as with the attribute. > > @Tom: > Will you update the compiler headers within this release cycle? > Otherwise we should take the patch as is to get us closer to the > -Wimplicit-fallthrough target.
I'm not going to update it for this release cycle. I've done the initial import and build and there's some fairly large changes related to inlining that I want to look at harder to see if we can/should do something about (I don't want to derail this thread, I'll start another). But it's very far from zero size change and given the inline changes I think it'll need real testing.
And since the kernel isn't making a huge use yet of fallthrough; we can afford to look a little harder at things.
I think I've figured out the inline issue which is that we need scripts/Kconfig.include from the kernel, CC_HAS_ASM_INLINE Kconfig option, and re-sync with Kconfiglib, but that's still going to be enough stuff that I don't think it's good to pull in at -rc2.
I do not get how 'asm inline' support is related to this topic.
GCC 9 started to support 'asm inline' for the better inlining heuristic. The kernel uses a bunch of inline assembly that is not as expensive as it looks.
As GCC is agnostic about the real cost of inline assembly, 'asm inline' is a good hint if people know the real cost is quite small. Then, GCC will be able to inline more functions.
I do not know how important it is for U-Boot, though.
What is causing you a trouble?
So, it turns out that while we do want to grab the changes so that we can have CC_HAS_ASM_INLINE via Kconfig, it's not "it". What I see for virtually every board (with gcc-9.3 from kernel.org) is something like: rock960-rk3399 : all -8 rodata -4 spl/u-boot-spl:all +992 spl/u-boot-spl:text +992 text -4 u-boot: add: 67/-9, grow: 74/-92 bytes: 5072/-4928 (144) function old new delta static._compare_and_overwrite_entry - 348 +348 menu_interactive_choice - 288 +288 hex2bin - 200 +200 __fswab64 - 176 +176 __fswab32 - 144 +144 sdhci_reset - 136 +136 dwmci_fifo_ready - 124 +124 fdt_offset_ptr_ - 120 +120 menu_items_iter - 108 +108 generic_fls - 100 +100 fdt_set_totalsize - 96 +96 static.generic_fls - 84 +84
OK, these functions previously disappeared because all of the function call-sites were inlined.
If you resync <linux/compier*.h> with latest Linux, they are not necessarily inlined.
In current U-Boot, 'static inline' is actually replaced with __attribute__((always_inline)). So, inlining is forcible.
See the code.
include/linux/compiler-gcc.h
#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4) #define inline inline __attribute__((always_inline)) notrace #define __inline__ __inline__ __attribute__((always_inline)) notrace #define __inline __inline __attribute__((always_inline)) notrace
In Linux, the following commits stopped doing that. (both my commits)
ac7c3e4ff401b304489a031938dbeaab585bfe0a 889b3c1245de48ed0cacf7aebb25c489d3e4a3e9
Now, 'inline' is just a compiler hint. The compiler does the best judge whether to inline the function or not.
Ah, OK. And the kernel is uninterested in bringing back forcing inlineing for size reasons as it's gone for LTO instead of ffunction-sections/fdata-sections and discarding sections (and we're in turn a ways off from that as we need to move to gcc linking) I assume. Thanks!
Digging more still, it's not a universal choice. On full U-Boot, it's around 90% a size win to let the compiler make the inline choice. On SPL it's more like 50%. I think I'm leaning towards making it a choice especially until we can figure out what would lead to better SPL results for everyone.
On Sat, May 09, 2020 at 05:12:42PM +0200, Heinrich Schuchardt wrote:
GCC recognizes /* fallthrough */ if -Wimplicit-fallthrough=3 is enabled. Let's use it consistently.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de
Applied to u-boot/master, thanks!
participants (3)
-
Heinrich Schuchardt -
Masahiro Yamada -
Tom Rini