ghc-9.12: The GHC API
Safe HaskellNone
LanguageGHC2021

GHC.CmmToAsm.Instr

Synopsis

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.

mkSpillInstr Source #

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.

mkLoadInstr Source #

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.

mkRegRegMoveInstr Source #

Arguments

:: NCGConfig 
-> Format 
-> Reg

source register

-> Reg

destination register

-> instr 

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

Instances details
Instruction Instr Source #

Instruction instance for aarch64

Instance details

Defined in GHC.CmmToAsm.AArch64

Instruction Instr Source #

Instruction instance for powerpc

Instance details

Defined in GHC.CmmToAsm.PPC

Instruction Instr Source #

Instruction instance for RV64

Instance details

Defined in GHC.CmmToAsm.RV64

Instruction Instr Source #

Instruction instance for x86 instruction set.

Instance details

Defined in GHC.CmmToAsm.X86

Instruction instr => Instruction (InstrSR instr) Source # 
Instance details

Defined in GHC.CmmToAsm.Reg.Liveness

data RegUsage Source #

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 

Instances

Instances details
Outputable RegUsage Source # 
Instance details

Defined in GHC.CmmToAsm.RV64.Instr

Methods

ppr :: RegUsage -> SDoc 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.

RegUsage = RU [regs] [regs]

Instance details

Defined in GHC.CmmToAsm.AArch64.Instr

Methods

ppr :: RegUsage -> SDoc Source #

Show RegUsage Source # 
Instance details

Defined in GHC.CmmToAsm.Instr

noUsage :: RegUsage Source #

No regs read or written to.