Displaying 20 results from an estimated 9000 matches similar to: "[LLVMdev] inline asm question"
2009 Aug 03
2
[LLVMdev] inline asm question
Eli Friedman wrote:
> 2009/8/2 Richard Pennington <rich at pennware.com>:
>> The following fails on x86_64 because of the output constraint '0'.
>> My question is, is this legal. LLVM complains about the size difference
>> (32 vs 64), but it is the same register (ax).
>> Works on x86.
>>
>> %42 = call i64 asm sideeffect
2009 Aug 03
0
[LLVMdev] inline asm question
2009/8/2 Richard Pennington <rich at pennware.com>:
> Eli Friedman wrote:
>> 2009/8/2 Richard Pennington <rich at pennware.com>:
>>> The following fails on x86_64 because of the output constraint '0'.
>>> My question is, is this legal. LLVM complains about the size difference
>>> (32 vs 64), but it is the same register (ax).
>>>
2009 Aug 03
0
[LLVMdev] inline asm question
2009/8/2 Richard Pennington <rich at pennware.com>:
> The following fails on x86_64 because of the output constraint '0'.
> My question is, is this legal. LLVM complains about the size difference
> (32 vs 64), but it is the same register (ax).
> Works on x86.
>
> %42 = call i64 asm sideeffect "syscall\0A\09",
>
2020 Jan 07
2
Inline assembly in intel syntax mishandling i constraint
Hi all,
I'm getting rather odd behavior from a call asm inteldialect(). TL;DR is "mov reg, $0" with a "i" constraint on $0 is behaving identical to "mov reg, dword ptr [$0]" and differently from "movl $0, reg" in AT&T syntax.
I'm not sure how to get clang to emit an inteldialect, so for this example, I'm emitting llvm and then modifying
2020 Jan 08
2
Inline assembly in intel syntax mishandling i constraint
> On Jan 7, 2020, at 18:41, Craig Topper <craig.topper at gmail.com> wrote:
>
> What version of llvm are you using? This looks like it may be fixed on trunk.
After poking at my installation of rust, I'm not entirely sure what version of LLVM it uses. Looking at the GitHub page, it looks like Rust maintains their own copy of llvm and cherry picks commits. The C example was
2013 Jun 07
2
[LLVMdev] add Inline assembly in LLVM IR
Hi all,
I'm working for translating dex bytecode to LLVM IR
In order to communicate with Android interpreter,
The work have to add data below some instructions
I want to use inline assembly to add data.
Thus, I wrote a little program to find out the related LLVM IR
int main()
{
asm(".long 0x12345678");
return 0;
}
and I use clang to translate it into bitcode
It's the
2011 May 17
1
[LLVMdev] inline asm
Are there any examples for the inline assembler or more complete docs?
Questions:
* What are the syntax and semantics of constraints?
* If I load up specific registers in the inline assembly, will llvm make
sure that those registers are unassigned or should I save the registers and
restore them? i.e. does llvm try and understand what is going on in the
inline assembly, or is it a black box to
2019 Dec 09
4
IR inline assembly: the x86 Intel "offset" operator
Hi all,
I'm trying to land (a rebased version of) http://llvm.org/D37461 - which
should make it possible to handle x86 Intel assembly like
mov eax, offset Foo::ptr + 1
(Currently, omitting the +1 works... but offset doesn't work in compound
expressions.)
I'm having trouble figuring out what inline assembly I can emit into the
LLVM IR that will work properly. So far, the closest
2009 Jul 31
0
[LLVMdev] Inserting Instructions (pass)
On Jul 31, 2009, at 10:24 AM, Michael Graumann wrote:
> Hi,
> I’ am trying to insert an InlineAsm Instruction in my pass, which
> FunctionType do I need for Inlineasm?
> If I understand it right, I need a call instruction to insert the
> new produced InlineAsm?
>
> Thanks for help
Inline asm works like a "callee". So for:
call void asm sideeffect
2008 Jun 06
0
[LLVMdev] Trouble with inline asm
On Fri, Jun 6, 2008 at 6:32 AM, Tomas Lindquist Olsen
<tomas.l.olsen at gmail.com> wrote:
> Hi all,
>
> I'm having some trouble with inline asm expressions, more specifically
> how to create the right FunctionType for a given constraint set.
> So far it has worked well for inputs, but not for outputs. The inline
> asm support in this language (which is D, LLVMDC[1]) is
2009 Jul 31
2
[LLVMdev] Inserting Instructions (pass)
Hi,
I' am trying to insert an InlineAsm Instruction in my pass, which
FunctionType do I need for Inlineasm?
If I understand it right, I need a call instruction to insert the new
produced InlineAsm?
Thanks for help,
Michael
for (BasicBlock::iterator bi = i->begin(), be = i->end(); bi != be; ++bi){
std::vector<const Type*> asm_arguments;
2009 Dec 22
1
[LLVMdev] is there a compiler barrier that is effective at codegen level?
Hi,
I would like to prevent that two adjacent calls to external functions getting
interleaved/separated by other neighboring code. This mixing seems to happen
in the code generator. I can prevent it by putting the two calls into a
separate BB, but then I can't use -simplifycfg, -jump-threading, ... as is.
Here is an example:
%160 = add i64 %158, %159 ; <i64>
2015 Nov 18
2
Meaning of IR inline assembly
Hello,
Most of the IR language is correctly explained; but with inline assembly I feel alone at some point:
define i32 @main(i32 %argc, i8** %argv) #0 {
... //some uninteresting bloat here
call void asm sideeffect "outw %eax, $0", "imr,~{dirflag},~{fpsr},~{flags}"(i32 %8) #2, !srcloc !2
ret i32 0
}
I reduced the above code to the offending line containing:
2008 Jun 06
2
[LLVMdev] Trouble with inline asm
Hi all,
I'm having some trouble with inline asm expressions, more specifically
how to create the right FunctionType for a given constraint set.
So far it has worked well for inputs, but not for outputs. The inline
asm support in this language (which is D, LLVMDC[1]) is through asm
*statements*.
I never have inline asm *expressions*, and outputs are always via memory.
I D my test looks like
2013 Jun 26
1
[LLVMdev] Inline asm call argument mismatch?
Hello,
In the following code snippet:
%tmp49 = call i64 asm "movq %gs:${1:P},$0", "=r,im,,~{fpsr},~{flags}"(i64*
@kernel_stack) #6, !dbg !6625, !srcloc !5841
I would expect for the inline asm call to receive two arguments because of
the ${1:P} corresponding to a %P1 that will append the $1 to %%gs:.
Can someone explain why there is only one argument in this call?
Moreover,
2015 Nov 18
2
Meaning of IR inline assembly
Thanks, but I could not find the imr, dirflag, fpsr constraints here. Just the usual gcc/clang inline assembly constraints.
Those one were of my concern, actually :)
--
Alex
18.11.2015, 17:11, "David Siegel" <agnat at icloud.com>:
>> On 18.11.2015, at 16:28, AlexandreFressange via llvm-dev <llvm-dev at lists.llvm.org> wrote:
>>
>> I reduced the above
2016 Oct 11
2
Landing Pad bug?
HI,
When compiling the open-source software cryptopp (https://www.cryptopp.com/#download <https://www.cryptopp.com/#download>) version 5.6.4 I found a strange issue with the IR generated.
The issue only appears when compiling with -O2 optimisation in the integer.cpp file (the function is _ZN8CryptoPPrsERNSt3__113basic_istreamIcNS0_11char_traitsIcEEEERNS_7IntegerE ->
2009 Aug 01
2
[LLVMdev] Inserting Instructions (pass)
Thank you Chris,
for your hint, but I am still too stupid. I tried two versions
asm_arguments.push_back(Type::VoidTy);
FunctionType *asm_type = FunctionType::get(Type::VoidTy, asm_arguments,
false);
Alternatively
FunctionType *asm_type = FunctionType::get(Type::VoidTy, std::vector<const
Type*>(), false);
. Can you give me a snippet of example code, or somebody else?
2018 Feb 08
2
retpoline mitigation and 6.0
On Wed, 2018-02-07 at 15:47 -0800, Craig Topper wrote:
> I'll save you a review iteration. This is updated to match llvm
> coding style. Capital camel case variable names and uses
> LLVM_FALLTHROUGH instead of the comment.
Thanks. How's this for a test?
; RUN: llc < %s -mtriple=i686-- -no-integrated-as | FileCheck -check-prefix=X86 %s
; RUN: llc < %s -mtriple=x86_64--
2015 Jul 29
2
[LLVMdev] optimizer clobber EFLAGS
Using Clang/LLVM 3.6.0 we are observing a case where the optimizations
are clobbering EFLAGS on x86_64. This is inconvenient when the status
of bit 9 (IF), which controls interrupts, changes.
Here's a simple test program. Assume that the external function foo()
modifies the IF bit in EFLAGS.
---
#include <stdlib.h>
#include <stdbool.h>
void foo(void);
int a;
int bar(void)