1 //===- MVEGatherScatterLowering.cpp - Gather/Scatter lowering -------------===//
9 /// This pass custom lowers llvm.gather and llvm.scatter instructions to
10 /// arm.mve.gather and arm.mve.scatter intrinsics, optimising the code to
48 #define DEBUG_TYPE "arm-mve-gather-scatter-lowering"
67     return "MVE gather/scatter lowering";  in getPassName()
81   // Check this is a valid gather with correct alignment
97   // Compute the scale of this gather/scatter instruction
108   // Create a gather from a base + vector of offsets
112   // Create a gather from a vector of pointers
116   // Create an incrementing gather from a vector of pointers
140   // gather/scatter
165                 "MVE gather/scattering lowering pass", false, false)
192   // vector with element types smaller or equal the type of the gather we're  in checkOffsetSize()
194   // to fit into the gather type.  in checkOffsetSize()
393   // Check that the constant is small enough for an incrementing gather  in getVarAndConst()
406   // @llvm.masked.gather.*(Ptrs, alignment, Mask, Src0)  in lowerGather()
407   // Attempt to turn the masked gather in I into a MVE intrinsic  in lowerGather()
445     // If this was an extending gather, we need to get rid of the sext/zext  in lowerGather()
446     // sext/zext as well as of the gather itself  in lowerGather()
449   LLVM_DEBUG(dbgs() << "masked gathers: successfully built masked gather\n"  in lowerGather()
503   // The size of the gather was already checked in isLegalTypeAndAlignment;  in tryCreateMaskedGatherOffset()
509       // If the gather has a single extend of the correct type, use an extending  in tryCreateMaskedGatherOffset()
510       // gather and replace the ext. In which case the correct root to replace  in tryCreateMaskedGatherOffset()
530     // extending gather and truncate back to the original type.  in tryCreateMaskedGatherOffset()
540     // The final size of the gather must be a full vector width  in tryCreateMaskedGatherOffset()
751                        "wb gather/scatter\n");  in tryCreateIncrementingGatScat()
763     // Only in this case do we want to build a wb gather, because the wb will  in tryCreateIncrementingGatScat()
772                        "non-wb gather/scatter\n");  in tryCreateIncrementingGatScat()
805   // Check whether this gather's offset is incremented by a constant - if so,  in tryCreateIncrementingWBGatScat()
806   // and the load is of the right type, we can merge this into a QI gather  in tryCreateIncrementingWBGatScat()
816     // one in the gather's gep  in tryCreateIncrementingWBGatScat()
854   // The gather is pre-incrementing  in tryCreateIncrementingWBGatScat()
867     // Build the incrementing gather  in tryCreateIncrementingWBGatScat()
869     // One value to be handed to whoever uses the gather, one is the loop  in tryCreateIncrementingWBGatScat()
871     EndResult = ExtractValueInst::Create(Load, 0, "Gather");  in tryCreateIncrementingWBGatScat()
1228     // used by an MVE gather; thus the offset has to have the correct size  in optimiseAddress()