search for: constantfold

Hi, I would like to nominate David Majnemer as the code owner for constant folding: lib/IR/ConstantFold.cpp. He seems to be the most active developer based on the git history. David do you accept? -Tom

Hi! in the llvm code there are several places with hardcoded function names for e.g. sin, sinf, sqrt, sqrtf etc., namely ConstantFolding.cpp InlineCost.cpp SelectionDAGBuilder.cpp IntrinsicLowering.cpp TargetLowering.cpp my question is: wouldn't it be beneficial to use intrinsics for this? for example a c/c++ frontend (clang) could translate the function calls to intrinsics and then in a very late step (IntrinsicLowering.c...

On Jul 7, 2010, at 5:47 AM, Jianzhou Zhao wrote: >> >> Does this also apply to two different variables? say >> int z x y; >> z = x ^ y; >> If ConstantFoldBinaryInstruction also folds x ^ y into z, should this >> pass (which uses ConstantFold) also initialize x and y with a same >> initial value? Otherwise at runtime z may not be 0. > > I guess my question is what variables can have undef values. In my > understanding, only unini...

...at 8:34 PM, Chris Lattner <clattner at apple.com> wrote: >> >> On Jul 6, 2010, at 3:37 PM, Jianzhou Zhao wrote: >> >>> Which semantics is better? I guess both are fine because if we assume >>> these two def's are same, then it is 0 as >>> 'ConstantFoldBinaryInstruction', while if we assume they are different >>> then it is equal to undef. But the second case seems to include the >>> first one. If we let undef xor undef to be undef, later we can use >>> this undef as 0, but also other values w.r.t contexts. Is there...

...anyway. Bug 10368 [1] tells me that ConstantExpr shouldn't automatically fold, and that this is source of many problems (most notably with traps) and code duplication. However, I'm a bit lost... There seem to be constant folding in many places like ConstantExpr::get*() uses lib/Analysis/ConstantFolding.cpp, that uses lib/VMCore/ConstantFold.cpp InstCombine also has some instruction simplification (duh), but it mostly deal with variables, so it only returns a semantically and simpler equivalent operation, rather than go all the way to fold if both arguments are constants (I guess). So, is the...

On Tue, Jul 6, 2010 at 8:34 PM, Chris Lattner <clattner at apple.com> wrote: > > On Jul 6, 2010, at 3:37 PM, Jianzhou Zhao wrote: > >> Which semantics is better? I guess both are fine because if we assume >> these two def's are same, then it is 0 as >> 'ConstantFoldBinaryInstruction', while if we assume they are different >> then it is equal to undef. But the second case seems to include the >> first one. If we let undef xor undef to be undef, later we can use >> this undef as 0, but also other values w.r.t contexts. Is there any >>...

I can't upload my program due to confidentiality, but the problem is obvious. At lib/Analysis/ConstantFolding.cpp:646 Constant *C = ConstantExpr::getGetElementPtr(Ops[0], NewIdxs); if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) { if (Constant *Folded = ConstantFoldConstantExpression(CE, TD, TLI)) C = Folded; } The generated ConstantExpr C doesn't inherit the inBounds a...

Hi, >> in the llvm code there are several places with hardcoded function >> names for e.g. sin, sinf, sqrt, sqrtf etc., namely >> ConstantFolding.cpp >> InlineCost.cpp >> SelectionDAGBuilder.cpp >> IntrinsicLowering.cpp >> TargetLowering.cpp >> >> my question is: wouldn't it be beneficial to use intrinsics for this? >> for example a c/c++ >> frontend (clang) could translate the function...

Hi, At line 2292, lib/VMCore/ConstantFold.cpp (llvm2.7 release) Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, Constant *C1, Constant *C2) { ... // Handle UndefValue up front. if (isa<UndefValue>(C1) || isa<UndefValue>(C2)) { switch (Opcode) { case Ins...

On Jul 6, 2010, at 3:37 PM, Jianzhou Zhao wrote: > Which semantics is better? I guess both are fine because if we assume > these two def's are same, then it is 0 as > 'ConstantFoldBinaryInstruction', while if we assume they are different > then it is equal to undef. But the second case seems to include the > first one. If we let undef xor undef to be undef, later we can use > this undef as 0, but also other values w.r.t contexts. Is there any > reason that Con...

On Wed, Jul 7, 2010 at 11:38 AM, Chris Lattner <clattner at apple.com> wrote: > > On Jul 7, 2010, at 5:47 AM, Jianzhou Zhao wrote: > >>> >>> Does this also apply to two different variables? say >>>   int z x y; >>>   z = x ^ y; >>> If ConstantFoldBinaryInstruction also folds x ^ y into z, should this >>> pass (which uses ConstantFold) also initialize x and y with a same >>> initial value? Otherwise at runtime z may not be 0. >> >> I guess my question is what variables can have undef values. In my >> unders...

...nable it from front-end (Clang in this case). > > I'm doing this for ARM platform and the flag should be reachable from > all these places in LLVM: > > A - lib/Analysis/ValueTracking.cpp > A - lib/CodeGen/SelectionDAG/SelectionDAG.cpp > A - lib/IR/ConstantFold.cpp > A - lib/Target/ARM/ARMFastISel.cpp > A - lib/Target/ARM/ARMISelLowering.cpp > A - lib/Target/ARM/ARMInstrVFP.td (through predicates) > A - lib/Target/ARM/ARMRegisterInfo.td (through predicates) > > and in Clang: > > A - lib/AST/ExprConst...

And another try for constant folding of Instructions for nvc0. Please Review this! Thanks, Tobias Klausmann Tobias Klausmann (4): nvc0/ir: clear subop when folding constant expressions nvc0/ir: Handle reverse subop for OP_EXTBF when folding constant expressions nvc0/ir: Handle OP_BFIND when folding constant expressions nvc0/ir: Handle OP_POPCNT when folding constant expressions

On Fri, 02 Mar 2012 13:55:18 +0100 Jochen Wilhelmy <jochen.wilhelmy at googlemail.com> wrote: > Hi! > > in the llvm code there are several places with hardcoded function > names for e.g. sin, sinf, sqrt, sqrtf etc., namely > ConstantFolding.cpp > InlineCost.cpp > SelectionDAGBuilder.cpp > IntrinsicLowering.cpp > TargetLowering.cpp > > my question is: wouldn't it be beneficial to use intrinsics for this? > for example a c/c++ > frontend (clang) could translate the function calls to intrinsics and >...

...; > >> I'm doing this for ARM platform and the flag should be reachable from > >> all these places in LLVM: > >> > >> A - lib/Analysis/ValueTracking.cpp > >> A - lib/CodeGen/SelectionDAG/SelectionDAG.cpp > >> A - lib/IR/ConstantFold.cpp > >> A - lib/Target/ARM/ARMFastISel.cpp > >> A - lib/Target/ARM/ARMISelLowering.cpp > >> A - lib/Target/ARM/ARMInstrVFP.td (through predicates) > >> A - lib/Target/ARM/ARMRegisterInfo.td (through predicates) > >> > >> an...

...st*, char const&, std::_Rb_tree_iterator<std::pair<std::pair<llvm::Type const*, char> const, llvm::UndefValue*> >) (in /home/gabi/vgen/Debug/vgen) ==20504==    by 0x8853A3: llvm::UndefValue::get(llvm::Type const*) (in /home/gabi/vgen/Debug/vgen) ==20504==    by 0x927DBA: llvm::ConstantFoldBinaryInstruction(unsigned int, llvm::Constant*, llvm::Constant*) (in /home/gabi/vgen/Debug/vgen) ==20504==    by 0x88BD87: llvm::ConstantExpr::getTy(llvm::Type const*, unsigned int, llvm::Constant*, llvm::Constant*, unsigned int) (in /home/gabi/vgen/Debug/vgen) ==20504==    by 0x423B2E: llvm::Const...

Chris Lattner wrote: > URL: http://llvm.org/viewvc/llvm-project?rev=81845&view=rev > Log: > fix PR4963: folding insertvalue would sometimes turn a packed struct into > an unpacked one. About this bug -- it happened because ConstantStruct::get has a default parameter for whether the struct should be packed or not, which defaults to not packed. This is strikingly error prone. We

...--git a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp index 6a4ea4e..dc048e6 100644 --- a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp +++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp @@ -451,7 +451,9 @@ ConstantFolding::expr(Instruction *i, b->data.f32 = 0.0f; } switch (i->dType) { - case TYPE_F32: res.data.f32 = a->data.f32 * b->data.f32; break; + case TYPE_F32: + res.data.f32 = a->data.f32 * b->data.f32 * exp2f(i->postFactor); + break;...

...vm::Type const*) constin libLLVMScalarOpts.a(GVN.cpp.o) llvm::TargetData::getTypeStoreSize(llvm::Type const*) constin libLLVMAnalysis.a(BasicAliasAnalysis.cpp.o) SymbolicallyEvaluateGEP(llvm::Constant* const*, unsigned int, llvm::Type const*, llvm::TargetData const*)in libLLVMAnalysis.a(ConstantFolding.cpp.o) llvm::TargetData::getTypeStoreSize(llvm::Type const*) constin libLLVMAnalysis.a(ConstantFolding.cpp.o) llvm::TargetData::getTypeStoreSize(llvm::Type const*) constin libLLVMSelectionDAG.a(DAGCombiner.cpp.o) llvm::TargetData::getTypeStoreSize(llvm::Type const*) constin lib...

I am using llvm-2.6 and the ConstProp.cpp file is http://llvm.org/docs/doxygen/html/ConstantProp_8cpp_source.html and the exact error message is: llvm[0]: Compiling ConstantProp.cpp for Release build (PIC) /home/tarun/Desktop/compiler/LLVM/llvm-2.6/include/llvm/Analysis/ConstantFolding.h: In member function ‘virtual bool<unnamed>::ConstantPropagation::runOnFunction(llvm::Function&)’: /home/tarun/Desktop/compiler/LLVM/llvm-2.6/include/llvm/Analysis/ConstantFolding.h:32: error: too few arguments to function ‘llvm::Constant* llvm::ConstantFoldInstruction(llvm::Instructi...