diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/llvm/Target/TargetRegisterInfo.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/include/llvm/Target/TargetRegisterInfo.h b/include/llvm/Target/TargetRegisterInfo.h index 958bea6f2b..5f50e402b9 100644 --- a/include/llvm/Target/TargetRegisterInfo.h +++ b/include/llvm/Target/TargetRegisterInfo.h @@ -672,6 +672,17 @@ public: // Do nothing. } + /// Allow the target to reverse allocation order of local live ranges. This + /// will generally allocate shorter local live ranges first. For targets with + /// many registers, this could reduce regalloc compile time by a large + /// factor. It should still achieve optimal coloring; however, it can change + /// register eviction decisions. It is disabled by default for two reasons: + /// (1) Top-down allocation is simpler and easier to debug for targets that + /// don't benefit from reversing the order. + /// (2) Bottom-up allocation could result in poor evicition decisions on some + /// targets affecting the performance of compiled code. + virtual bool reverseLocalAssignment() const { return false; } + /// requiresRegisterScavenging - returns true if the target requires (and can /// make use of) the register scavenger. virtual bool requiresRegisterScavenging(const MachineFunction &MF) const { |