1 //===- RISCVMatInt.h - Immediate materialisation ---------------*- C++ -*--===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_LIB_TARGET_RISCV_MCTARGETDESC_MATINT_H 10 #define LLVM_LIB_TARGET_RISCV_MCTARGETDESC_MATINT_H 11 12 #include "llvm/ADT/SmallVector.h" 13 #include "llvm/MC/SubtargetFeature.h" 14 #include <cstdint> 15 16 namespace llvm { 17 class APInt; 18 19 namespace RISCVMatInt { 20 struct Inst { 21 unsigned Opc; 22 int64_t Imm; 23 24 Inst(unsigned Opc, int64_t Imm) : Opc(Opc), Imm(Imm) {} 25 }; 26 using InstSeq = SmallVector<Inst, 8>; 27 28 // Helper to generate an instruction sequence that will materialise the given 29 // immediate value into a register. A sequence of instructions represented by a 30 // simple struct is produced rather than directly emitting the instructions in 31 // order to allow this helper to be used from both the MC layer and during 32 // instruction selection. 33 InstSeq generateInstSeq(int64_t Val, const FeatureBitset &ActiveFeatures); 34 35 // Helper to estimate the number of instructions required to materialise the 36 // given immediate value into a register. This estimate does not account for 37 // `Val` possibly fitting into an immediate, and so may over-estimate. 38 // 39 // This will attempt to produce instructions to materialise `Val` as an 40 // `Size`-bit immediate. 41 // 42 // If CompressionCost is true it will use a different cost calculation if RVC is 43 // enabled. This should be used to compare two different sequences to determine 44 // which is more compressible. 45 int getIntMatCost(const APInt &Val, unsigned Size, 46 const FeatureBitset &ActiveFeatures, 47 bool CompressionCost = false); 48 } // namespace RISCVMatInt 49 } // namespace llvm 50 #endif 51