1 //===-- GuardUtils.h - Utils for work with guards ---------------*- 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 // Utils that are used to perform transformations related to guards and their 9 // conditions. 10 //===----------------------------------------------------------------------===// 11 12 #ifndef LLVM_TRANSFORMS_UTILS_GUARDUTILS_H 13 #define LLVM_TRANSFORMS_UTILS_GUARDUTILS_H 14 15 namespace llvm { 16 17 class BranchInst; 18 class CallInst; 19 class Function; 20 class Value; 21 22 /// Splits control flow at point of \p Guard, replacing it with explicit branch 23 /// by the condition of guard's first argument. The taken branch then goes to 24 /// the block that contains \p Guard's successors, and the non-taken branch 25 /// goes to a newly-created deopt block that contains a sole call of the 26 /// deoptimize function \p DeoptIntrinsic. If 'UseWC' is set, preserve the 27 /// widenable nature of the guard by lowering to equivelent form. If not set, 28 /// lower to a form without widenable semantics. 29 void makeGuardControlFlowExplicit(Function *DeoptIntrinsic, CallInst *Guard, 30 bool UseWC); 31 32 /// Given a branch we know is widenable (defined per Analysis/GuardUtils.h), 33 /// widen it such that condition 'NewCond' is also known to hold on the taken 34 /// path. Branch remains widenable after transform. 35 void widenWidenableBranch(BranchInst *WidenableBR, Value *NewCond); 36 37 /// Given a branch we know is widenable (defined per Analysis/GuardUtils.h), 38 /// *set* it's condition such that (only) 'Cond' is known to hold on the taken 39 /// path and that the branch remains widenable after transform. 40 void setWidenableBranchCond(BranchInst *WidenableBR, Value *Cond); 41 42 } // llvm 43 44 #endif // LLVM_TRANSFORMS_UTILS_GUARDUTILS_H 45