search for: unsignedness

Hey everyone, I'm trying to retrieve information about signed-/unsignedness of an llvm::Argument so I can print out it's value to the user properly. llvm itself doesn't distinguish signed and unsigned and so llvm::Type is of no help here. Checking for nsw/usw is only an unreliable approximation and only available for llvm::Instructions anyways. I tried to use...

...cation if metadata could be attached to arguments. I'm currently working around it by using named metadata in the module (matched by index to the arguments). Andrew On 02/21/2011 11:18 AM, Florian Merz wrote: > Hey everyone, > > I'm trying to retrieve information about signed-/unsignedness of an > llvm::Argument so I can print out it's value to the user properly. llvm itself > doesn't distinguish signed and unsigned and so llvm::Type is of no help here. > Checking for nsw/usw is only an unreliable approximation and only available > for llvm::Instructions anyways....

...lly nothing wrong with such combination, and code works fine until I ran debug llvm for some other reason and this assert showed up. So if I need to shift signed int8 with unsigned uint32, I have to first truncate shift to uint8, with understanding that uint8 will become int8 because llvm lacks unsignedness? I think such requirement is redundant and you should make an exception in shift operator definitions to allow for any combination of numeric arguments. It forces to create an extra trunc/expand operator without the real need. Yuri

Hi there, [ http://www.contribs.org/bugzilla/show_bug.cgi?id=654 ] I just received this: Broadcast message from nut (Sat Feb 4 04:02:45 2006): UPS UPS@localhost battery is low and Feb 4 04:02:45 bigted upsmon[11532]: UPS UPS@localhost battery is low Feb 4 04:02:45 bigted wall[4032]: wall: user nut broadcasted 1 lines (34 chars) but I believe this looks o.k., except for the input voltage

I get an assert @ Instructions.cpp:1774 when Op=llvm::Instruction::Shl. Should this assert avoid shift operations? Yuri

Hi Yuri, As stated in LLVM's language reference manual (http://llvm.org/docs/LangRef.html#i_shl), both arguments for a shl need to have the same type. What exactly are you trying to do? --Stephan > I get an assert @ Instructions.cpp:1774 when Op=llvm::Instruction::Shl. > Should this assert avoid shift operations? > > Yuri

...for (unsigned long i = 0; i < length; i++) array[3 * length - i] = array[i]; } For there to be a loop carried dependency, we'd have to have (3 * length / 2) < length which we know doesn't hold, since length is always positive. Unfortunately, the LLVM IR tell us nothing about the unsignedness of length, and SCEV ends up making a useless conservative estimate. Is there some way around this? Secondly, I'm currently comparing A and B by creating an SCEV for (A - B) and then checking isZero, isKnownNonPositive etc. Is this a good idea? Thanks! [1] https://github.com/sanjoy/llvm/tre...

Hello, I was doing some experiments with SCEV and especially the loop trip count. Sorry for the dumb question, what is the easiest way to dump SCEV analysis results on a .bc file? On a side note, I wanted to see if we could optimize this function: unsigned long kernel(long w, long h, long d) { unsigned long count = 0; for(int i = 0; i < w; ++i) for(int j = i; j < h; ++j) for(int k = j; k

...Remove a dead condition. taskmgr: Remove redundant out-of-domain checking which is already handled by PerfDataGetProcessorUsage() and PerfDataGetProcessorSystemUsage(). kernel32/tests: Remove extraneous check. winex11.drv: Simplify condition in create_xcursor_cursor() based on the unsignedness of types. msi: Simplify condition in TABLE_fetch_stream(). d3d9/tests: Simplify condition in test_vshader_input(). wined3d: Remove four noop checks. winspool: Adjust the typo of a loop variable in test_EnumForms(). ole32: Remove one noop check in CoWaitForMultipleHandl...

...ch combination, and code works fine > until I ran debug llvm for some other reason and this assert showed up. > > So if I need to shift signed int8 with unsigned uint32, I have to first > truncate shift to uint8, with understanding that uint8 will become int8 > because llvm lacks unsignedness? > I think such requirement is redundant and you should make an exception > in shift operator definitions to allow for any combination of numeric > arguments. It forces to create an extra trunc/expand operator without > the real need. > > Yuri > > > ----------------...

...gt; to arguments. I'm currently working around it by using named metadata > in the module (matched by index to the arguments). > > Andrew > > On 02/21/2011 11:18 AM, Florian Merz wrote: >> Hey everyone, >> >> I'm trying to retrieve information about signed-/unsignedness of an >> llvm::Argument so I can print out it's value to the user properly. llvm itself >> doesn't distinguish signed and unsigned and so llvm::Type is of no help here. >> Checking for nsw/usw is only an unreliable approximation and only available >> for llvm::Instru...