Implement lowering of the Mul/Div operations and also shift parts
operations. Implement lowering of the bit manipulations, like
ROT/SWAP/CTPOP/CTTZ/CTLZ.
This patch implements lowering of the GlobalAddress, BlockAddress,
JumpTable and BR_JT. Also patch adds legal support of the BR_CC
operation for i32 type.
Implement emitPrologue/emitEpilogue methods, determine/spill/restore
callee saved registers functionality with test. Also implement lowering
of the DYNAMIC_STACKALLOC/STACKSAVE/STACKRESTORE stack operations with
tests.
This PR provides implementation of the basic codegen infra such as
TargetFrameLowering, MCInstLower,
AsmPrinter, RegisterInfo, InstructionInfo, TargetLowering,
SelectionDAGISel.
Migrated from https://reviews.llvm.org/D145658
