Justin Bogner e1037058df GlobalISel: Make MachineCSE runnable in the middle of the GlobalISel ... Right now, it is not possible to run MachineCSE in the middle of the GlobalISel pipeline. Being able to run generic optimizations between the core passes of GlobalISel was one of the goals of the new ISel framework. This is the first attempt to do it. The problem is that MachineCSE pass assumes all register operands have a register class, which, in GlobalISel context, won't be true until after the InstructionSelect pass. The reason for this behaviour is that before replacing one virtual register with another, MachineCSE pass (and most of the other optimization machine passes) must check if the virtual registers' constraints have a (sufficiently large) intersection, and constrain the resulting register appropriately if such intersection exists. GlobalISel extends the representation of such constraints from just a register class to a triple (low-level type, register bank, register class). This commit adds MachineRegisterInfo::constrainRegAttrs method that extends MachineRegisterInfo::constrainRegClass to such a triple. The idea is that going forward we should use: - RegisterBankInfo::constrainGenericRegister within GlobalISel's InstructionSelect pass - MachineRegisterInfo::constrainRegClass within SelectionDAG ISel - MachineRegisterInfo::constrainRegAttrs everywhere else regardless the target and instruction selector it uses. Patch by Roman Tereshin. Thanks! llvm-svn: 322805		2018-01-18 02:06:56 +00:00
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llvm	GlobalISel: Make MachineCSE runnable in the middle of the GlobalISel	2018-01-18 02:06:56 +00:00
llvm-c	Debug Info: Support DW_AT_calling_convention on composite types.	2018-01-05 01:13:37 +00:00