| Safe Haskell | None |
|---|---|
| Language | GHC2021 |
GHC.CmmToAsm.Instr
Synopsis
- class Instruction instr where
- regUsageOfInstr :: Platform -> instr -> RegUsage
- patchRegsOfInstr :: Platform -> instr -> (Reg -> Reg) -> instr
- isJumpishInstr :: instr -> Bool
- jumpDestsOfInstr :: instr -> [BlockId]
- canFallthroughTo :: instr -> BlockId -> Bool
- patchJumpInstr :: instr -> (BlockId -> BlockId) -> instr
- mkSpillInstr :: NCGConfig -> RegWithFormat -> Int -> Int -> [instr]
- mkLoadInstr :: NCGConfig -> RegWithFormat -> Int -> Int -> [instr]
- takeDeltaInstr :: instr -> Maybe Int
- isMetaInstr :: instr -> Bool
- mkRegRegMoveInstr :: NCGConfig -> Format -> Reg -> Reg -> instr
- takeRegRegMoveInstr :: Platform -> instr -> Maybe (Reg, Reg)
- mkJumpInstr :: BlockId -> [instr]
- mkStackAllocInstr :: Platform -> Int -> [instr]
- mkStackDeallocInstr :: Platform -> Int -> [instr]
- pprInstr :: Platform -> instr -> SDoc
- mkComment :: FastString -> [instr]
- data RegUsage = RU {
- reads :: [RegWithFormat]
- writes :: [RegWithFormat]
- noUsage :: RegUsage
Documentation
class Instruction instr where Source #
Common things that we can do with instructions, on all architectures. These are used by the shared parts of the native code generator, specifically the register allocators.
Methods
regUsageOfInstr :: Platform -> instr -> RegUsage Source #
Get the registers that are being used by this instruction. regUsage doesn't need to do any trickery for jumps and such. Just state precisely the regs read and written by that insn. The consequences of control flow transfers, as far as register allocation goes, are taken care of by the register allocator.
patchRegsOfInstr :: Platform -> instr -> (Reg -> Reg) -> instr Source #
Apply a given mapping to all the register references in this instruction.
isJumpishInstr :: instr -> Bool Source #
Checks whether this instruction is a jump/branch instruction. One that can change the flow of control in a way that the register allocator needs to worry about.
jumpDestsOfInstr :: instr -> [BlockId] Source #
Give the possible *local block* destinations of this jump instruction. Must be defined for all jumpish instructions.
canFallthroughTo :: instr -> BlockId -> Bool Source #
Check if the instr always transfers control flow to the given block. Used by code layout to eliminate jumps that can be replaced by fall through.
patchJumpInstr :: instr -> (BlockId -> BlockId) -> instr Source #
Change the destination of this jump instruction. Used in the linear allocator when adding fixup blocks for join points.
Arguments
| :: NCGConfig | |
| -> RegWithFormat | the reg to spill |
| -> Int | the current stack delta |
| -> Int | spill slots to use |
| -> [instr] | instructions |
An instruction to spill a register into a spill slot.
Arguments
| :: NCGConfig | |
| -> RegWithFormat | the reg to reload. |
| -> Int | the current stack delta |
| -> Int | the spill slot to use |
| -> [instr] | instructions |
An instruction to reload a register from a spill slot.
takeDeltaInstr :: instr -> Maybe Int Source #
See if this instruction is telling us the current C stack delta
isMetaInstr :: instr -> Bool Source #
Check whether this instruction is some meta thing inserted into the instruction stream for other purposes.
Not something that has to be treated as a real machine instruction and have its registers allocated.
eg, comments, delta, ldata, etc.
Copy the value in a register to another one. Must work for all register classes.
takeRegRegMoveInstr :: Platform -> instr -> Maybe (Reg, Reg) Source #
Take the source and destination from this reg -> reg move instruction or Nothing if it's not one
mkJumpInstr :: BlockId -> [instr] Source #
Make an unconditional jump instruction. For architectures with branch delay slots, its ok to put a NOP after the jump. Don't fill the delay slot with an instruction that references regs or you'll confuse the linear allocator.
mkStackAllocInstr :: Platform -> Int -> [instr] Source #
mkStackDeallocInstr :: Platform -> Int -> [instr] Source #
pprInstr :: Platform -> instr -> SDoc Source #
Pretty-print an instruction
mkComment :: FastString -> [instr] Source #
Instances
Holds a list of source and destination registers used by a particular instruction.
Machine registers that are pre-allocated to stgRegs are filtered out, because they are uninteresting from a register allocation standpoint. (We wouldn't want them to end up on the free list!)
As far as we are concerned, the fixed registers simply don't exist (for allocation purposes, anyway).
Constructors
| RU | |
Fields
| |
Instances
| Outputable RegUsage Source # | |
| Outputable RegUsage Source # | Get the registers that are being used by this instruction. regUsage doesn't need to do any trickery for jumps and such. Just state precisely the regs read and written by that insn. The consequences of control flow transfers, as far as register allocation goes, are taken care of by the register allocator. |
| Show RegUsage Source # | |