Displaying 20 results from an estimated 20000 matches similar to: "RFC: We need to explicitly state that some functions are reserved by LLVM"
2017 Oct 27
5
RFC: We need to explicitly state that some functions are reserved by LLVM
On Fri, Oct 27, 2017 at 1:50 AM, David Chisnall via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> This seems slightly inverted. As I understand it, the root of the problem
> is that some standards, such as C, C++, and POSIX, define some functions as
> special and we rely on their specialness when optimising. Unfortunately,
> the specialness is a property of the source
2016 Feb 08
2
LoopIdiomRegognize vs Preserved
Hi,
I'm having problems with the LoopIdiomRegognizer crashing on me with
An asserting value handle still pointed to this value!
UNREACHABLE executed at ../lib/IR/Value.cpp:695!
If I remove
AU.addPreserved<LoopInfoWrapperPass>();
or
AU.addPreserved<AAResultsWrapperPass>();
everything goes well.
The C-code triggering this is
void foo(int a[10][10])
{
int i, j,
2010 Aug 02
2
[LLVMdev] indirectbr and phi instructions
Hi,
How does the requirement that phi instructions have one value per
predecessor basic block interact with indirectbr instructions? For
instance, take the following code:
L1:
br i1 %somevalue, label %L2, label %L3
L2:
%ret1 = i8* blockaddress(@myfunction, %L5)
br label %L4
L3:
%ret2 = i8* blockaddress(@myfunction, %L6)
br label %L4
L4:
%ret = phi i8* [%ret1, L2], [%ret2, L3]
2020 Jan 07
2
Let CallGraphSCCPass Use Function-Level Analysis
Dear all,
I would like to use the PostDominatorTree in ArgPromotion. I did not find an example of how to use function level analysis inside CallGraphSCCPass. I tried to follow an example of how to use function-level pass in a module pass, but I hit "llvm_unreachable" in PMDataManager::addLowerLevelRequiredPass.
What would be a proper way to make PostDominatorTree available in
2011 Jan 25
2
[LLVMdev] Update PHINode after extracting code
Hi all,
I have problem with ExtractCodeRegion (CodeExtractor.cpp).
My original program is as follows.
bb:
...
%tmp.15 = load %struct.MYSQL_ROWS** %3, align 4
...
bb1:
...
%tmp.1 = load %struct.MYSQL_ROWS** %6, align 4
...
bb4: ; preds = %bb1, %bb,
%entry
%tmp.0 = phi %struct.MYSQL_ROWS* [ null, %entry ], [ %tmp.15, %bb ], [
%tmp.1, %bb1 ]
2012 Jul 25
2
[LLVMdev] Question about an unusual jump instruction
Dear all,
I'm working on an exploratory backend on llvm. In the instruction set I'm using
I have an instruction (called DECJNZ) that decrements a register and, if the
decremented value is not zero, jumps (with a relative jump) to a given offset.
I've described in tablegen this instruction as follow:
def DECJNZ : Instruction {
let Namespace = "MyTarget";
let
2012 Jul 25
0
[LLVMdev] Question about an unusual jump instruction
On Wed, Jul 25, 2012 at 12:48 AM, Michele Scandale
<michele.scandale at gmail.com> wrote:
> Dear all,
>
> I'm working on an exploratory backend on llvm. In the instruction set I'm using
> I have an instruction (called DECJNZ) that decrements a register and, if the
> decremented value is not zero, jumps (with a relative jump) to a given offset.
>
> I've
2015 Mar 24
2
[LLVMdev] RFC - Improvements to PGO profile support
Example. Assuming the cap is 'C'
void bar()
{
// ENTRY count is 4*C, after capping it becomes 'C'
...
}
void test()
{
// BB1: count(BB1) = C
bar();
// BB2: count(BB2) = C
bar();
}
void test2()
{
// BB3: count(BB3) = C
bar();
// BB4: count(BB4) = C
bar();
}
What would inliner see here ? When it sees callsite1 -- it might mistaken
that is the
2010 Jul 17
2
[LLVMdev] How to insert a basic block in an edge
Hi all,
Suppose in a CFG bb1 has two succesor bb3 and bb4, and bb3 has two
predecessor bb1 and bb2. Now how can I insert a basic block between
bb1 and bb3 that at the edge bb1-->bb3 .
In general how can I insert a basic block on an edge?
Regards,
Chayan
2010 Nov 17
1
[LLVMdev] Copy Instruction from one Basic block to another
I want to do the following:
suppose the program structure:
bb
/ \
bb1 bb2
\ /
bb3
2010 Jul 18
2
[LLVMdev] How to insert a basic block in an edge
Hi,
I have tried to use SplitEdge function, but failed. Actually the third
parameter is a variable of type Pass and it need to be non-null. But I
could not figure out how to use it. Please help me out.
Regards,
Chayan
On Sat, Jul 17, 2010 at 10:16 PM, Nick Lewycky <nicholas at mxc.ca> wrote:
> Chayan Sarkar wrote:
>>
>> Hi all,
>>
>> Suppose in a CFG bb1 has two
2016 Sep 21
2
Propagation of debug information for variable into basic blocks.
> On Sep 21, 2016, at 2:23 PM, Daniel Berlin <dberlin at dberlin.org> wrote:
>
>
>
> // For all predecessors of this MBB, find the set of VarLocs that
> // can be joined.
> for (auto p : MBB.predecessors()) {
> auto OL = OutLocs.find(p);
> // Join is null in case of empty OutLocs from any of the pred.
> if (OL == OutLocs.end())
>
2009 Sep 03
2
[LLVMdev] Non-local DSE optimization
Hi,
It looks like PDT.getRootNode() returns NULL for:
define fastcc void @c974001__lengthy_calculation.
1736(%struct.FRAME.c974001* nocapture %CHAIN.185) noreturn {
entry:
br label %bb
bb:
br label %bb
}
Isn't it a bug in PostDominatorTree?
Please note that this crashes:
opt -postdomtree -debug dom_crash.bc
I think this should be reported as a bug,
-Jakub
On Sep 3, 2009, at
2011 Nov 21
1
[LLVMdev] Fwd: Order of Basic Blocks
---------- Forwarded message ----------
From: Ryan Taylor <ryta1203 at gmail.com>
Date: Mon, Nov 21, 2011 at 10:30 AM
Subject: Re: [LLVMdev] Order of Basic Blocks
To: Benjamin Kramer <benny.kra at googlemail.com>
This worked, though the RPO_iterator apparently wasn't what I was looking
for anyways, it seems it doesn't rreally go top->down.
I have a simple example code,
2020 Jan 07
2
Let CallGraphSCCPass Use Function-Level Analysis
Hi Mikhail,
As Brian noted, stuff like this works better in the new pass manager.
Even in the old pass manager I thought it should work though.
Did you initialize the pass, via
`INITIALIZE_PASS_DEPENDENCY(PostDominatorTreeWrapperPass)`?
Did you require it, via
` AU.addRequired<PostDominatorTreeWrapperPass>();`?
Btw. May I ask what you are planning to do?
Cheers,
Johannes
On 01/07,
2013 Oct 10
2
[LLVMdev] Are there implicit rules or conventions for an llvm frontend to generate llvm IR?
Hi, this question might be a bit silly: apart from the language
reference(http://llvm.org/docs/LangRef.html#switch-instruction) page, are
there additional rules for a regular llvm frontend to generate llvm IRs?
There are a few cases that I got from clang/llvm-gcc/dragonegg when
compiling *C* source code into llvm IR:
1. It seems that there is ONLY ONE ReturnInst(and NO InvokeInst) for such
llvm
2009 Sep 03
0
[LLVMdev] Non-local DSE optimization
Hi Jakub, interesting patch. I ran it over the Ada testsuite and this
picked up some problems even without enabling dse-ssu. For example,
"opt -inline -dse -domtree" crashes on the attached testcase.
Ciao,
Duncan.
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: dom_crash.ll
URL:
2010 Jul 20
2
[LLVMdev] How to insert a basic block in an edge
Hi All,
Still I could not figure out how to use Pass* while calling
SplitEdge() function. Can anyone provide me some example?
Regards,
Chayan
On Sun, Jul 18, 2010 at 11:49 PM, Nick Lewycky <nicholas at mxc.ca> wrote:
> Chayan Sarkar wrote:
>>
>> Hi,
>>
>> I have tried to use SplitEdge function, but failed. Actually the third
>> parameter is a variable of
2010 Jun 29
0
[LLVMdev] Confuse on getSCEVAtScope
On Jun 29, 2010, at 7:08 AM, ether zhhb wrote:
>
> why computeSCEVAtScope not try to get the operands in the current
> scope like the function do with SCEVCommutativeExpr, like:
>
> if (const SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(V)) {
> if (!L || !AddRec->getLoop()->contains(L)) {
> ...
> // Then, evaluate the AddRec.
>
2009 Aug 31
2
[LLVMdev] Non-local DSE optimization
Hello,
This patch adds non-local DSE optimization. It uses Static Single Use
representation. This is my first "big" patch, please be tolerant :-)
Please note that optimization is disabled by default.
-Jakub
-------------- next part --------------
A non-text attachment was scrubbed...
Name: dse_ssu.patch
Type: application/octet-stream
Size: 17352 bytes
Desc: not available
URL: