search for: __bss_start

Hi, I am writing a function that clears the BSS section on an Cortex-M4 embedded system. The LLVM (version 3.7.0rc3) code I had wrote is : ;------------ target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64" target triple = "thumbv7em-none--eabi" @__bss_start = external global i32 @__bss_end = external global i32 define void @clearBSS () nounwind { entry: br label %bssLoopTest bssLoopTest: %p = phi i32* [@__bss_start, %entry], [%p.next, %bssLoop] %completed = icmp eq i32* %p, @__bss_end br i1 %completed, label %clearCompleted, label %bssLoo...

Hi Nick, We have few symbols like __bss_start, __bss_end, which are Undefined symbols in the code. I want a way in the Reader to create specific atoms before the linker bootstraps. I didnt find a way to do that with the existing interfaces. The way it needs to work is as below :- 1) ReaderELF creates Absolute symbols (for __bss_start, __...

On Dec 7, 2012, at 11:51 AM, Shankar Easwaran wrote: > We have few symbols like __bss_start, __bss_end, which are Undefined symbols in the code. > > I want a way in the Reader to create specific atoms before the linker bootstraps. > > I didnt find a way to do that with the existing interfaces. > > The way it needs to work is as below :- > > 1) ReaderELF creates...

...The key here is that the Pass (not written yet) which sorts atoms, knows to sort these atoms to the start or end of their respective sections. > > If you don't want this full general, lazy approach, you could have your WriteELF::addFiles() return a regular object file that has atoms named __bss_start and __bss_end, but they are marked mergeAsWeak so that any user defined atoms will override them. The case I have is a bit different now. I added symbols __bss_start/__bss_end/_end using WriterELF::addFiles(). The symbols get overridden appropriately but the value of the symbols are known only a...

...d too, any pointers to how you are doing that will be helpful. If not, I need to duplicate that piece of code, which doesnot make sense. Thanks Shankar Easwaran On 12/7/2012 4:59 PM, Nick Kledzik wrote: > On Dec 7, 2012, at 11:51 AM, Shankar Easwaran wrote: >> We have few symbols like __bss_start, __bss_end, which are Undefined symbols in the code. >> >> I want a way in the Reader to create specific atoms before the linker bootstraps. >> >> I didnt find a way to do that with the existing interfaces. >> >> The way it needs to work is as below :- >> &...

...- HIDDEN(__pm_code_end = .); - HIDDEN(__pm_code_len = ABSOLUTE(__pm_code_end) - ABSOLUTE(__pm_code_start)); - HIDDEN(__pm_code_dwords = (__pm_code_len + 3) >> 2); - - . = ALIGN(128); - - HIDDEN(__bss_vma = .); - HIDDEN(__bss_lma = .); /* Dummy */ - .bss (NOLOAD) : AT (__bss_lma) { - HIDDEN(__bss_start = .); - *(.bss) - *(.bss.*) - *(COMMON) - HIDDEN(__bss_end = .); - } - HIDDEN(__bss_len = ABSOLUTE(__bss_end) - ABSOLUTE(__bss_start)); - HIDDEN(__bss_dwords = (__bss_len + 3) >> 2); - - /* Data saved away before bss initialization */ - . = ALIGN(128); - - HIDDEN(__savedata_vma = .); - HI...

From: Sylvain Gault <sylvain.gault at gmail.com> These patches basically remove unused linker scripts and port a change that was made to an unused script. Those are to be applied on top of the gcc 5 bug fixes as they would conflict otherwise. Sylvain Gault (4): diag/mbr: fix dependency to linker script Remove unused linker scripts core: Make symbols defined in linker script HIDDEN

Is there a required Clang and LLVM version one needs to do a ''make xen-dist clang=y''? I recently tried and the process failed. I haven''t begun debugging as I figured I would ask the obvious first. The build failed with the following: ... make[4]: Entering directory `/home/builder/xen-unstable/xen/drivers'' make -f /home/builder/xen-unstable/xen/Rules.mk -C char

...== R_X86_64_64) add_reloc(&relocs64, offset); diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S index 5077ead5e59c..4418ff0a1d96 100644 --- a/arch/x86/xen/xen-head.S +++ b/arch/x86/xen/xen-head.S @@ -28,14 +28,15 @@ ENTRY(startup_xen) /* Clear .bss */ xor %eax,%eax - mov $__bss_start, %_ASM_DI - mov $__bss_stop, %_ASM_CX + _ASM_MOVABS $__bss_start, %_ASM_DI + _ASM_MOVABS $__bss_stop, %_ASM_CX sub %_ASM_DI, %_ASM_CX shr $__ASM_SEL(2, 3), %_ASM_CX rep __ASM_SIZE(stos) - mov %_ASM_SI, xen_start_info - mov $init_thread_union+THREAD_SIZE, %_ASM_SP + _ASM_MOVABS $xen_start_in...

...inux.ld b/efi/i386/syslinux.ld index 523a9b9..bab3fc7 100644 --- a/efi/i386/syslinux.ld +++ b/efi/i386/syslinux.ld @@ -136,7 +136,7 @@ SECTIONS *(.strtab) } - .bss : { + .bss (NOLOAD) : { /* the EFI loader doesn't seem to like a .bss section, so we stick it all into .data: */ __bss_start = .; @@ -153,7 +153,7 @@ SECTIONS __bss_dwords = (__bss_len + 3) >> 2; . = ALIGN(128); - + /* Very large objects which don't need to be zeroed */ .hugebss : { diff --git a/efi/wrapper.c b/efi/wrapper.c index 4839e52..1988124 100644 --- a/efi/wrapper.c +++ b/efi/wrapper.c @@ -...

...inux.ld b/efi/i386/syslinux.ld index 523a9b9..bab3fc7 100644 --- a/efi/i386/syslinux.ld +++ b/efi/i386/syslinux.ld @@ -136,7 +136,7 @@ SECTIONS *(.strtab) } - .bss : { + .bss (NOLOAD) : { /* the EFI loader doesn't seem to like a .bss section, so we stick it all into .data: */ __bss_start = .; @@ -153,7 +153,7 @@ SECTIONS __bss_dwords = (__bss_len + 3) >> 2; . = ALIGN(128); - + /* Very large objects which don't need to be zeroed */ .hugebss : { diff --git a/efi/wrapper.c b/efi/wrapper.c index 9652368..a5247ae 100644 --- a/efi/wrapper.c +++ b/efi/wrapper.c @@ -...

...start, __irqentry_text_end > * __softirqentry_text_start, __softirqentry_text_end > */ > +#ifdef CONFIG_DEFAULT_HIDDEN > +#pragma GCC visibility push(default) > +#endif > extern char _text[], _stext[], _etext[]; > extern char _data[], _sdata[], _edata[]; > extern char __bss_start[], __bss_stop[]; > @@ -46,6 +49,9 @@ extern char __softirqentry_text_start[], __softirqentry_text_end[]; > > /* Start and end of .ctors section - used for constructor calls. */ > extern char __ctors_start[], __ctors_end[]; > +#ifdef CONFIG_DEFAULT_HIDDEN > +#pragma GCC visibil...

...start, __irqentry_text_end > * __softirqentry_text_start, __softirqentry_text_end > */ > +#ifdef CONFIG_DEFAULT_HIDDEN > +#pragma GCC visibility push(default) > +#endif > extern char _text[], _stext[], _etext[]; > extern char _data[], _sdata[], _edata[]; > extern char __bss_start[], __bss_stop[]; > @@ -46,6 +49,9 @@ extern char __softirqentry_text_start[], __softirqentry_text_end[]; > > /* Start and end of .ctors section - used for constructor calls. */ > extern char __ctors_start[], __ctors_end[]; > +#ifdef CONFIG_DEFAULT_HIDDEN > +#pragma GCC visibil...

...not present in it's public header (for a total of 85 symbols, see attach). Would it make sense to filter them via -fvisibility=hidden and -Wl,--version-script? I attached a draft patch. Best regards, Yury Gribov -------------- next part -------------- _book_maptype1_quantvals _book_unquantize __bss_start drft_backward drft_clear drft_forward drft_init _edata _end _fini _float32_pack _float32_unpack floor0_exportbundle floor1_encode floor1_exportbundle floor1_fit floor1_interpolate_fit _floor_P _init _make_words mapping0_exportbundle _mapping_P mdct_backward mdct_clear mdct_forward mdct_init ov_ilog...

...; * __softirqentry_text_start, __softirqentry_text_end >> */ >> +#ifdef CONFIG_DEFAULT_HIDDEN >> +#pragma GCC visibility push(default) >> +#endif >> extern char _text[], _stext[], _etext[]; >> extern char _data[], _sdata[], _edata[]; >> extern char __bss_start[], __bss_stop[]; >> @@ -46,6 +49,9 @@ extern char __softirqentry_text_start[], __softirqentry_text_end[]; >> >> /* Start and end of .ctors section - used for constructor calls. */ >> extern char __ctors_start[], __ctors_end[]; >> +#ifdef CONFIG_DEFAULT_HIDDEN >&gt...

The PE headers of the generated efi file were quite buggy. And since OVMF perform a few consistency checks, syslinux was unable to run on it. I don't pretend to have a thorough understanding of the PE+ headers, some bugs may remain. :) Celelibi (4): efi: Fix PE header field rva_and_sizes_nr efi: Location, size and alignment of .text section efi: Useless relocations in PE file efi: PE

...h @@ -30,6 +30,9 @@ * __irqentry_text_start, __irqentry_text_end * __softirqentry_text_start, __softirqentry_text_end */ +#ifdef CONFIG_DEFAULT_HIDDEN +#pragma GCC visibility push(default) +#endif extern char _text[], _stext[], _etext[]; extern char _data[], _sdata[], _edata[]; extern char __bss_start[], __bss_stop[]; @@ -46,6 +49,9 @@ extern char __softirqentry_text_start[], __softirqentry_text_end[]; /* Start and end of .ctors section - used for constructor calls. */ extern char __ctors_start[], __ctors_end[]; +#ifdef CONFIG_DEFAULT_HIDDEN +#pragma GCC visibility pop +#endif extern __vi...

...4bit toy kernel (based on Mini-OS as starting point) for xen and I run into problems with the way the start of day sets up the physical pages. My kernel is mapped at 0 (due to Mini-OS being there): _text : 0x0 _etext : 0xcaef _edata : 0xe8c4 __bss_start : 0x10000 _end : 0x21590 nr_pages : 3072 start_info : 0x27000 pt_base : 0x2a000 nr_pt_frames : 5 machine_to_phys_mapping: 0xffff800000000000 phys_to_machine_mapping: 0x21000 The Mini-OS source says that...

This series: 1. Updates the boot protocol to version 2.07 2. Clean up the existing build process, to get rid of tools/build and make the linker do more heavy lifting 3. Make the bzImage payload an ELF file. The bootloader can extract this as a naked ELF file by skipping over boot_params.setup_sects worth of 16-bit setup code. 4. Update the boot_params to 2.07, and update the

This series: 1. Updates the boot protocol to version 2.07 2. Clean up the existing build process, to get rid of tools/build and make the linker do more heavy lifting 3. Make the bzImage payload an ELF file. The bootloader can extract this as a naked ELF file by skipping over boot_params.setup_sects worth of 16-bit setup code. 4. Update the boot_params to 2.07, and update the