Displaying 20 results from an estimated 900 matches similar to: "[LLVMdev] indirect jumps"
2010 Apr 15
1
[LLVMdev] Question About Cloning Machine Basic Block
Hello,
I am trying to clone a machine basic block when I ran into some issues, where I am not able to make some headway. Any of yours help is highly appreciated here:
My question is about Machine Basic Block Duplication:
- Is there a utility to clone a MachineBasicBlock in LLVM? I found utility to clone machineInstrs, but couldn’t find similar utility for MachineBasicBlock. So, I
2012 Nov 29
0
[LLVMdev] radr://12777299, "potential pthread/eh bug exposed by libsanitizer"
I debugged this a bit and it seems the mach_override patching of __cxa_throw is bogus. The start of that function is patched to jump to garbage.
Breakpoint 1, 0x0000000100001c19 in main ()
(gdb) display/i $pc
2: x/i $pc 0x100001c19 <main+318>: callq 0x100016386 <dyld_stub___cxa_throw>
(gdb) si
0x0000000100016386 in dyld_stub___cxa_throw ()
2: x/i $pc 0x100016386
2010 Jun 17
2
[LLVMdev] Relocation issue with jump tables in ELF object files on X86_64
(llvm 2.6)
We have an application where we are using LLVM to generate ELF object files for X86_64. At runtime we load these objects files into memory using our own ELF loader.
Everything is working except for the jump tables.
The ELF emitter is generating JMPQ instructions using X86::reloc_absolute_word_sext relocations which we are unable to patch to the jump table in the .rodata segment
2016 Nov 22
2
Conditional jump or move depends on uninitialised value(s)
Just want to emphasize that on x86-64 and using Valgrind:
LLVM compiled with LLVM gets 360 unexpected test fails
LLVM compiled with GCC gets 22 unexpected test fails
Of course I don't know how many of these are caused by this bitfield
speculation issue.
John
On 11/21/2016 10:48 PM, regehr via llvm-dev wrote:
> Alright, here's what seems to be happening...
>
> The testcase
2012 Oct 24
0
[LLVMdev] dyld: lazy symbol binding failed: fast lazy bind offset out of range
On Oct 23, 2012, at 4:46 PM, Jack Howarth wrote:
> On Tue, Oct 23, 2012 at 02:03:15PM -0700, Nick Kledzik wrote:
>>
>> On Oct 23, 2012, at 1:57 PM, Jack Howarth wrote:
>>> Nick,
>>> Can I do this without access to a debug version of dyld? Using the copy of LLVMPolly.so with isl/cloog-isl/gmp statically linked,
>>> I find that if I set the breakpoint to
2008 Oct 31
3
[LLVMdev] nested function's static link gets clobbered
Fellow developers,
I'm parallelizing loops to be called by pthread. The thread body that I pass
to pthread_create looks like
define i8* @loop1({ i32*, i32* }* nest %parent_frame, i8* %arg)
parent_frame is pointer to shared variables in original function
0x00007f0de11c41f0: mov (%r10),%rax
0x00007f0de11c41f3: cmpl $0x63,(%rax)
0x00007f0de11c41f6: jg 0x7f0de11c420c
2012 Nov 30
2
[LLVMdev] radr://12777299, "potential pthread/eh bug exposed by libsanitizer"
On Fri, Nov 30, 2012 at 01:41:05PM +0400, Kostya Serebryany wrote:
> Just want to remind everyone that we plan to stop using mach_override in
> asanin favor of OSX's native function interposition.
> So, we probably don't want to spend too much effort fixing mach_override.
>
> --kcc
Kostya,
Is the native function interposition that is being adopted based on...
2012 Nov 30
3
[LLVMdev] radr://12777299, "potential pthread/eh bug exposed by libsanitizer"
Looks like this happens on x86_64 because the position of __cxa_throw
is too far from the allocated branch island (should be <2G). This can
be solved by allocating the branch islands somewhere near the text
segment (look for kIslandEnd in asan_mac.cc, this is currently
0x7fffffdf0000) or by patching the function with a longer instruction
sequence that stores the jump target in a register and
2010 Jun 17
0
[LLVMdev] Relocation issue with jump tables in ELF object files on X86_64
On Thu, Jun 17, 2010 at 12:38 PM, Smith, Tim <tim at bioware.com> wrote:
> (llvm 2.6)
>
>
>
> We have an application where we are using LLVM to generate ELF object files
> for X86_64. At runtime we load these objects files into memory using our
> own ELF loader.
>
>
>
> Everything is working except for the jump tables.
>
>
>
> The ELF emitter is
2014 Sep 11
2
[LLVMdev] Fail to load a pointer to a function inside MCJIT-ed code when it is reload from ObjectCache
Hi, All
I have a problem to reuse mcjit jitted code loaded from ObjectCache from a
file. In the first run, I use MCJIT generate function JittedOpExpr object
code as following and it runs OK. 0x7fe4801fa1f8 at instruction
0x00007fe4cc6c2014 points to 0x69382E which is the beginning of ExecEvalVar
function. Then I save the object code into a file after implementing
notifyObjectCompiled method.
2012 Nov 30
0
[LLVMdev] radr://12777299, "potential pthread/eh bug exposed by libsanitizer"
Just want to remind everyone that we plan to stop using mach_override in
asanin favor of OSX's native function interposition.
So, we probably don't want to spend too much effort fixing mach_override.
--kcc
On Fri, Nov 30, 2012 at 4:46 AM, Alexander Potapenko <glider at google.com>wrote:
> Looks like this happens on x86_64 because the position of __cxa_throw
> is too far from
2008 Nov 01
0
[LLVMdev] nested function's static link gets clobbered
Hi,
> I'm parallelizing loops to be called by pthread. The thread body that I pass
> to pthread_create looks like
>
> define i8* @loop1({ i32*, i32* }* nest %parent_frame, i8* %arg)
> parent_frame is pointer to shared variables in original function
>
> 0x00007f0de11c41f0: mov (%r10),%rax
> 0x00007f0de11c41f3: cmpl $0x63,(%rax)
> 0x00007f0de11c41f6:
2016 Jun 22
2
x86: How to Force 2-byte `jmp` instruction in lowering
I have a bit of a riddle:
In http://reviews.llvm.org/D19904 I'm trying to spell the following
assembly:
.palign 2, 0x90
jmp +0x9
nopw 512(%rax,%rax,1)
// rest of the code
I try the following snippet to accomplish this:
OutStreamer->EmitLabel(CurSled);
OutStreamer->EmitCodeAlignment(4);
auto Target = OutContext.createLinkerPrivateTempSymbol();
// Use a two-byte `jmp`.
2015 Jul 24
2
[LLVMdev] [LLD] support for dlltool generated libs in COFF/PECOFF
After some more digging and creating a few testcases in lld I have narrowed
it down to
The fact that dlltool generates
Contents of section .idata$7:
0000 55534552 33322e64 6c6c0000 USER32.dll..
Where as lld expects
Contents of section .idata$6:
0000 55534552 33322e64 6c6c0000 USER32.dll..
I recreated the hello64.test using dlltool for the lib and here is the
asm dump of
2010 Jun 17
2
[LLVMdev] Relocation issue with jump tables in ELF object files on X86_64
I had this problem a while back and received this response from Jeffrey. FWIW this is fixed in 2.7 by defaulting to CodeModel::Large and using indirect (far) calls.
-----Original Message-----
From: Jeffrey Yasskin [mailto:jyasskin at google.com]
Sent: Monday, December 07, 2009 11:32 AM
To: Howell, Nathan
Cc: LLVM Developers Mailing List
Subject: Re: [LLVMdev] 2.6 JIT using wrong address for
2012 Dec 01
1
[LLVMdev] radr://12777299, "potential pthread/eh bug exposed by libsanitizer"
On Sat, Dec 01, 2012 at 05:42:15PM +0400, Kostya Serebryany wrote:
> +kremenek, ganna
>
> On Sat, Dec 1, 2012 at 4:33 AM, Jack Howarth <howarth at bromo.med.uc.edu>wrote:
>
> > On Fri, Nov 30, 2012 at 01:41:05PM +0400, Kostya Serebryany wrote:
> > > Just want to remind everyone that we plan to stop using mach_override in
> > > asanin favor of OSX's
2012 Dec 01
0
[LLVMdev] radr://12777299, "potential pthread/eh bug exposed by libsanitizer"
+kremenek, ganna
On Sat, Dec 1, 2012 at 4:33 AM, Jack Howarth <howarth at bromo.med.uc.edu>wrote:
> On Fri, Nov 30, 2012 at 01:41:05PM +0400, Kostya Serebryany wrote:
> > Just want to remind everyone that we plan to stop using mach_override in
> > asanin favor of OSX's native function interposition.
> > So, we probably don't want to spend too much effort fixing
2012 Dec 01
4
[LLVMdev] radr://12777299, "potential pthread/eh bug exposed by libsanitizer"
On Fri, Nov 30, 2012 at 01:41:05PM +0400, Kostya Serebryany wrote:
> Just want to remind everyone that we plan to stop using mach_override in
> asanin favor of OSX's native function interposition.
> So, we probably don't want to spend too much effort fixing mach_override.
>
> --kcc
Kostya,
Unless I am misunderstanding the code in asan/asan_intercepted_functions.h,
2014 Sep 11
2
[LLVMdev] Fail to load a pointer to a function inside MCJIT-ed code when it is reload from ObjectCache
Thank you Lang. I attached the ELF object file here for your reference.
Here is the IR dump of JittedOpExpr LLVM function. IrExprGetValue1 LLVM
function calls to external function expr->evalfunc(expr, econtext, isNull,
isDone); which should be pointed by 0x7fe4801fa1f8. However, only the first
time MCJIT generated object point to expr->evalfunc but second time when
program load from object
2017 Jun 04
2
trying to get a minimal windows program linked with lld
Here's some C code:
extern void *GetStdHandle(unsigned int nStdHandle);
extern void ExitProcess(unsigned int exit_code);
extern char WriteFile(void *HANDLE, const void * lpBuffer, unsigned int
nNumberOfBytesToWrite,
unsigned int *lpNumberOfBytesWritten, void *lpOverlapped);
static const char *message_ptr = "hello\n";
static const unsigned int message_len = 6;