Displaying 20 results from an estimated 4000 matches similar to: "Change function call name in a CallInst only in certain functions"
2018 Mar 24
0
Change function call name in a CallInst only in certain functions
You are probably calling setName() on the called Function, which in-turned renamed the called Function instead of replacing the called function.
Depending on your use-case, if you are certain that you only need to modify CallInsts, then you could simply call CallInst::setCalledFunction , otherwise it’s probably wiser to use CallSite as a wrapper for both CallInst and InvokeInst. Do note, however,
2018 May 22
2
DSE: Remove useless stores between malloc & memset
You might want to look more carefully at how you're constructing the
MemoryLocation. The first argument is a pointer, and the second
argument is the number of bytes pointed to by that pointer (or
MemoryLocation::UnknownSize if the number of bytes accessed isn't known).
More generally, copy-pasting code you don't understand isn't a good idea.
-Eli
On 5/22/2018 4:02 PM, Dávid
2018 May 22
2
DSE: Remove useless stores between malloc & memset
It works with
MemoryLocation MemoryLocation::get(const CallInst *CI) {
AAMDNodes AATags;
CI->getAAMetadata(AATags);
const auto &DL = CI->getModule()->getDataLayout();
return MemoryLocation(CI, DL.getTypeStoreSize(CI->getType()), AATags);
}
Is it fine? :)
2018-05-22 23:56 GMT+02:00 Dávid Bolvanský <david.bolvansky at gmail.com>:
> Looks like there are many overloads
2018 May 22
0
DSE: Remove useless stores between malloc & memset
Yeah, sorry for that. Better "It compiles ok (but maybe incorrect code)",
not "It works" as I wrote.
2018-05-23 1:08 GMT+02:00 Friedman, Eli <efriedma at codeaurora.org>:
> You might want to look more carefully at how you're constructing the
> MemoryLocation. The first argument is a pointer, and the second argument
> is the number of bytes pointed to by
2018 May 22
2
DSE: Remove useless stores between malloc & memset
Full stack trace:
opt: /home/xbolva00/LLVM/llvm/include/llvm/ADT/Optional.h:176: T*
llvm::Optional<T>::getPointer() [with T = llvm::MemoryLocation]: Assertion
`Storage.hasVal' failed.
Stack dump:
0. Program arguments: opt aaa.ll -dse -S
1. Running pass 'Function Pass Manager' on module 'aaa.ll'.
2. Running pass 'Dead Store Elimination' on function
2018 May 22
0
DSE: Remove useless stores between malloc & memset
IR:
define i32 @calloc_strlen_write_between() {
%call = tail call noalias i8* @calloc(i32 10, i32 1)
store i8 97, i8* %call, align 1
%call1 = tail call i32 @strlen(i8* %call)
ret i32 %call1
}
static bool eliminateStrlen(CallInst *CI, BasicBlock::iterator &BBI,
AliasAnalysis *AA, MemoryDependenceResults *MD,
const DataLayout &DL, const TargetLibraryInfo *TLI,
2018 May 22
0
DSE: Remove useless stores between malloc & memset
Looks like there are many overloads for "get".
http://llvm.org/doxygen/MemoryLocation_8cpp_source.html
But nothing for CallInst. Any suggestions how to do a proper one? I will
look at it too.
2018-05-22 23:34 GMT+02:00 Dávid Bolvanský <david.bolvansky at gmail.com>:
> Full stack trace:
>
> opt: /home/xbolva00/LLVM/llvm/include/llvm/ADT/Optional.h:176: T*
>
2018 May 22
2
DSE: Remove useless stores between malloc & memset
* if (isStringFromCalloc(Dst, TLI)) should be if (!isStringFromCalloc(Dst,
TLI))
but still asserting...
2018-05-22 23:06 GMT+02:00 Dávid Bolvanský <david.bolvansky at gmail.com>:
> Can you help a bit?
>
> I try to work with DSE but I got the following assert:
> opt: /home/xbolva00/LLVM/llvm/include/llvm/ADT/Optional.h:176: T*
> llvm::Optional<T>::getPointer() [with T
2018 May 21
2
DSE: Remove useless stores between malloc & memset
memoryIsNotModifiedBetween is precisely the sort of expensive walk we
shouldn't be doing... I'm surprised it hasn't caused any serious issues
yet. Ideally, what we should be doing is using MemorySSA to find a
dependency from the memset: if the closest dependency is the malloc,
there aren't any stores between the memset and the malloc. (But we
aren't using MemorySSA in
2011 Sep 16
2
[LLVMdev] How to duplicate a function?
Hi all,
Sorry for the inconvenient about the previous post. The files were not
attached. So I put them here again.
I am a newbie in LLVM and I am trying to replace the function like:
old function || new function
==============================
=========
int haha(int a) { int haha(int a, char* ID) {
===>
}
2006 Oct 31
2
[LLVMdev] callinst vs. invokeinst
What is the difference between a CallInst and an InvokeInst in LLVM? Is
an InvokeInst a CallInst that can throw an exception?
Thanks,
Ryan
2018 May 22
0
DSE: Remove useless stores between malloc & memset
It looks like the memoryIsNotModifiedBetween assumes the second argument
is a store, or some other instruction supported by MemoryLocation::get.
If you're passing in something else, you'll have to compute the
MemoryLocation some other way.
(Generally, if you're asking a question about an assertion, please
include the whole stack trace; it's hard to guess what's happening
2018 May 22
0
DSE: Remove useless stores between malloc & memset
Can you help a bit?
I try to work with DSE but I got the following assert:
opt: /home/xbolva00/LLVM/llvm/include/llvm/ADT/Optional.h:176: T*
llvm::Optional<T>::getPointer() [with T = llvm::MemoryLocation]: Assertion
`Storage.hasVal' failed.
static bool eliminateStrlen(CallInst *CI, BasicBlock::iterator &BBI,
AliasAnalysis *AA, MemoryDependenceResults
2008 Sep 13
3
[LLVMdev] Duplicate Function with duplicated Arguments
I'm now writing a pass and I wanna ask a question about how to
duplicate the function and add duplicated arguments in llvm, for
example:
func(int a, char *b) -> func(int a, char *b, int a1, char *b1)
I'm now stuck at using "getOrInsertFunction" and how to handle
"getArgumentList", please share your opinion, thanks a lot!
James
2018 Apr 20
2
Missed strlen optimizations
Use *last = nullptr;
for (Use &U : Src->uses())
last = &U;
last->getUser()->dump();
Or any better solution?
2018-04-20 19:19 GMT+02:00 Dávid Bolvanský <david.bolvansky at gmail.com>:
> Is:
>
>
> 2018-04-20 18:07 GMT+02:00 Dávid Bolvanský <david.bolvansky at gmail.com>:
>
>> Hello,
>>
>> Code: https://godbolt.org/g/EG4Wi6
2018 Apr 20
0
Missed strlen optimizations
Maybe nicer..
auto i = Src->uses().begin();
std::advance(i, Src->getNumUses() - 1);
i->getUser()->dump();
2018-04-20 19:19 GMT+02:00 Dávid Bolvanský <david.bolvansky at gmail.com>:
> Use *last = nullptr;
> for (Use &U : Src->uses())
> last = &U;
> last->getUser()->dump();
>
>
> Or any better solution?
>
> 2018-04-20 19:19
2018 May 09
3
Ignored branch predictor hints
Hello,
#define likely(x) __builtin_expect((x),1)
// switch like
char * b(int e) {
if (likely(e == 0))
return "0";
else if (e == 1)
return "1";
else return "f";
}
GCC correctly prefers the first case:
b(int):
mov eax, OFFSET FLAT:.LC0
test edi, edi
jne .L7
ret
But Clang seems to ignore _builtin_expect hints in this case.
2018 May 09
2
Ignored branch predictor hints
Hi Dávid,
Looks like you can defeat the switch conversion by adding a dummy asm(“”):
#define likely(x) __builtin_expect((x),1)
// switch like
char * b(int e) {
if (likely(e == 0))
return "0";
asm("");
if (e == 1)
return "1";
else return "f";
}
Dave
> On May 9, 2018, at 2:33 PM, Dávid Bolvanský via llvm-dev
2016 Mar 01
2
Insert CallInst within a function passing same parameters of the calling function.
Hi,
supposing I have a function “foo” like the following:
int foo(int a, int b) {
...
...
}
I want to insert int the LLVM IR a call instructions to a function “bar” that requires the same parameters of foo.
So my function foo will become:
int foo(int a, int b) {
bar(a,b);
…
...
}
I am using the following code:
bool ThreadSanitizer::runOnFunction(Function &F) {
2015 Sep 08
2
CallInst::getCalledFunction returns null?
I was wondering if someone could explain why CallInst::getCalledFunc behaves
the way it does.
For simple, direct call instructions in my IR, that method behaves just as
one would expect.
However, for instructions like this:
%25 = call i32 (%struct._IO_FILE*, ...)* bitcast (i32 (...)* @close to i32
> (%struct._IO_FILE*, ...)*)(%struct._IO_FILE* %24), !dbg !695
getCalledFunc returns null.
I