diff options
Diffstat (limited to 'include/llvm/CodeGen/MachineInstr.h')
-rw-r--r-- | include/llvm/CodeGen/MachineInstr.h | 35 |
1 files changed, 22 insertions, 13 deletions
diff --git a/include/llvm/CodeGen/MachineInstr.h b/include/llvm/CodeGen/MachineInstr.h index e7e728c1be28..8d040beff7a6 100644 --- a/include/llvm/CodeGen/MachineInstr.h +++ b/include/llvm/CodeGen/MachineInstr.h @@ -826,26 +826,35 @@ public: getOperand(0).getSubReg() == getOperand(1).getSubReg(); } - /// Return true if this is a transient instruction that is - /// either very likely to be eliminated during register allocation (such as - /// copy-like instructions), or if this instruction doesn't have an - /// execution-time cost. + /// Return true if this instruction doesn't produce any output in the form of + /// executable instructions. + bool isMetaInstruction() const { + switch (getOpcode()) { + default: + return false; + case TargetOpcode::IMPLICIT_DEF: + case TargetOpcode::KILL: + case TargetOpcode::CFI_INSTRUCTION: + case TargetOpcode::EH_LABEL: + case TargetOpcode::GC_LABEL: + case TargetOpcode::DBG_VALUE: + return true; + } + } + + /// Return true if this is a transient instruction that is either very likely + /// to be eliminated during register allocation (such as copy-like + /// instructions), or if this instruction doesn't have an execution-time cost. bool isTransient() const { - switch(getOpcode()) { - default: return false; + switch (getOpcode()) { + default: + return isMetaInstruction(); // Copy-like instructions are usually eliminated during register allocation. case TargetOpcode::PHI: case TargetOpcode::COPY: case TargetOpcode::INSERT_SUBREG: case TargetOpcode::SUBREG_TO_REG: case TargetOpcode::REG_SEQUENCE: - // Pseudo-instructions that don't produce any real output. - case TargetOpcode::IMPLICIT_DEF: - case TargetOpcode::KILL: - case TargetOpcode::CFI_INSTRUCTION: - case TargetOpcode::EH_LABEL: - case TargetOpcode::GC_LABEL: - case TargetOpcode::DBG_VALUE: return true; } } |