similar to: [LLVMdev] Using LLVM with clang for a homebrew kernel

Hi! I followed the discussion on structure types with the example struct I { int a; char b; }; struct J : I { char c; }; Dave said that this translates to %I = type { i32, i8, i16 } %J = type { %I, i8, i16 } because the frontend has to communicate the ABI to llvm since llvm is language agnostic. What I really wonder is why it isn't %I = type { i32, i8 } %J = type { %I, i16, i8

Am 29.12.2011 19:52, schrieb Reid Kleckner: > I think Chris is saying that the and is necessary because with your i1 > trunc you're ignoring all of the high bits. The and implements that. > If you don't want this behavior, don't generate the trunc in the > first place and just compare the full width to zero. But if a backend sees trunc from i8 to i1 it should know

> If %I is not a "POD for the purposes of layout" type, that it's tail > padding MUST be overlapped when inherited from. In this case, we > end up creating two types for %I, %I and %I' and use %I' as the > type when it is inherited from. > But this is the question why two types in this case. if %I = type { i32, i8 }; then %I has 8 bytes if used directly

>> What I really wonder is why it isn't >> >> %I = type { i32, i8 } >> %J = type { %I, i16, i8 } >> >> because llvm at least knows alignment rules by >> >> target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16... >> >> Therefore llvm has no other choice than assigning %I a size of 8 >> since an array may consist of %I

Hi! > sin/cos etc should already be handled by lib/Analysis/ConstantFolding.cpp. > Thanks for the hint and it works! Now I have a new Problem: I have this function: float foo(float a, float b) { float x = a * b * 0.0f; return cos(0.5) * sin(0.5) * x; }; after compiling it with clang (cpp mode) and renaming _ZSt3sinf to sin and _ZSt3cosf to cos I get the following: define

Hi! Of course nobody wants to implement unicode support for windows because windows should support an utf8-locale and windows is obsolete anyway ;-) But there is a simple solution: use boost::filesystem::path everywhere you use file names and paths, for example in clang::FileManager::getFile. With version 3 opening a file is easy: std::fstream file(path.c_str()). Internally

> If you're saying that: > > >> %I = type { i32, i8 }; >> > has size 5, yes, you're missing the alignment. > Ah, now I see. But I didn't say that %I = type { i32, i8 }; has 5 bytes (because it has 8) but I thought that it has 5 bytes when being a member of %J, i.e. %J = type { %I, i8 } In this case %I also has 8 bytes right? I was thinking

>> %I = type { i32, i8 }; // 5 bytes >> %I' = type { %I, tailpad}; // 8 bytes >> %J = type { %I, i8 } // 6 bytes >> > That would break C code (and whatever else relies on alignment). > why would it break C code? of course a C frontend should generate only tailpadded types. > I don't see a way of specifying two structures, but I like the idea of

On 25.11.2010 23:56, Michael Spencer wrote: > On Nov 25, 2010, at 5:01 PM, Jochen Wilhelmy <j.wilhelmy at arcor.de > <mailto:j.wilhelmy at arcor.de>> wrote: > >> Hi! >> >> Of course nobody wants to implement unicode support for windows >> because windows should support an utf8-locale and windows is obsolete >> anyway ;-) >> >> But

On Nov 25, 2010, at 5:01 PM, Jochen Wilhelmy <j.wilhelmy at arcor.de> wrote: > Hi! > > Of course nobody wants to implement unicode support for windows > because windows should support an utf8-locale and windows is obsolete > anyway ;-) > > But there is a simple solution: use boost::filesystem::path everywhere you > use file names and paths, for example in

Now I have -DLLVM_INCLUDE_EXAMPLES:BOOL=OFF but Kaleidoscope is still there and selected for build (-G "Visual Studio 9 2008") -Jochen

Hi! Is it possible that you add an example how to write a .o with llvm? Just like examples/ModuleMaker but instead of printing to stdout writing a .o file as starting point for the new MC functionality. -Jochen

Hi! In DataTypes.h (generated from DataTypes.cmake) there is an extra code path for Visual C. This can produce macro redefinitions for INT8_MAX, INT8_MIN etc. since other headers may also define them. Therefore please protect the macros like INT8_C etc. Also it would be nice if the auto-generated HAVE_STDINT_H and HAVE_INTTYPES_H would be used also for Visual C since it is possible to add them

On 3 March 2010 11:56, Jochen Wilhelmy <j.wilhelmy at arcor.de> wrote: > > the sin and cos calls are folded, but not the mul by zero. > Is x*0 => 0 true if isnan(x)? And cos(x)*sin(x) makes me desperately want to fold it to sin(2*x)/2, but I suppose that's not allowed either.

>> Hi! >> >> before InstCombine (llvm::createInstructionCombiningPass()) I have >> a trunc from i8 to i1 and then a select: >> >> %45 = load i8* @myGlobal, align 1 >> %tobool = trunc i8 %45 to i1 >> %cond = select i1 %tobool, float 1.000000e+00, float -1.000000e+00 >> >> after instCombine I have: >> >> %29 = load i8*

>> why would it break C code? of course a C frontend should generate only >> tailpadded types. >> > It's not about the size, but the offset. If you had a char field in > the inherited class: > > %I' = type { %I, i8, tailpad}; > > The offset of that i8 has to be 8, not 5. If all structures are > packed, that would be 5, which is correct for

Hello, A new patch: https://reviews.llvm.org/D47159 proposes transformations like: printf("Hello, %s %d", "world", 123) - > printf("Hello world 123") As Eli noted: "I'm not sure we can rewrite calls to varargs functions safely in general given the current state of the C ABI rules in LLVM. Sometimes clang does weird things to conform with the ABI

Thanks. Yes, to substitute only some of the arguments. Formatting used by printf depends on the locale but only for double, float types I think - yes, I would not place double/float constants into the format string. Why? To reduce number of constants (some of them could be merged into the format string) and number of args when calling printf/fprintf/sprintf, etc.. 2018-05-22 16:22 GMT+02:00 Hal

Hi! when compiling projects using llvm 2.9 and ms vc 10 I get these warnings: 1>e:\Jochen\Lib\lib\include\llvm/Use.h(218): warning C4624: 'llvm::AugmentedUse' : destructor could not be generated because a base class destructor is inaccessible 1>C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\include\stdint.h(72): warning C4005: 'INT8_MIN' : macro redefinition

Hello Jochen- Your expectation is incorrect, I'm afraid. Typically this would be expanded to something like this: … %cmp = … br i1 %cmp, label %ternary.true, label %ternary.false ternary.true: %truevalue = … br label %ternary.end ternary.false: %falsevalue = … br label %ternary.end ternary.end: %value = phi %type [%truevalue, %ternary.true], [%falsevalue,