Position Independent Code (PIC) support [1]

- Modified instruction format to handle pseudo instructions
- Added LoadAddr SDNode to load symbols.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42778 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bruno Cardoso Lopes 2007-10-09 02:55:31 +00:00
parent f6be158e9e
commit e78080c4dc
2 changed files with 44 additions and 18 deletions

View File

@ -42,6 +42,9 @@ class MipsInst<dag outs, dag ins, string asmstr, list<dag> pattern,
let Itinerary = itin;
}
// Mips Pseudo Instructions Format
class PseudoInstMips<dag outs, dag ins, string asmstr, list<dag> pattern>:
MipsInst<outs, ins, asmstr, pattern, IIPseudo>;
//===----------------------------------------------------------------------===//
// Format R instruction class in Mips : <|opcode|rs|rt|rd|shamt|funct|>
@ -98,3 +101,4 @@ class FJ<bits<6> op, dag outs, dag ins, string asmstr, list<dag> pattern,
let Inst{25-0} = addr;
}

View File

@ -24,7 +24,7 @@ def MipsJmpLink : SDNode<"MipsISD::JmpLink",SDT_MipsJmpLink, [SDNPHasChain,
// Hi and Lo nodes are created to let easy manipulation of 16-bit when
// handling 32-bit immediates. They are used on MipsISelLowering to
// lower stuff like GlobalAddress, ExternalSymbol, ...
// lower stuff like GlobalAddress, ExternalSymbol, ... on static model
// This two nodes have nothing to do with Mips Registers Hi and Lo.
def MipsHi : SDNode<"MipsISD::Hi", SDTIntUnaryOp, [SDNPOutFlag]>;
def MipsLo : SDNode<"MipsISD::Lo", SDTIntUnaryOp>;
@ -34,6 +34,9 @@ def MipsLo : SDNode<"MipsISD::Lo", SDTIntUnaryOp>;
def MipsAdd : SDNode<"MipsISD::Add", SDTIntBinOp, [SDNPCommutative,
SDNPAssociative, SDNPOptInFlag]>;
// Used to Load Addresses on PIC code.
def MipsLoadAddr: SDNode<"MipsISD::LoadAddr", SDTIntUnaryOp>;
// Return
def SDT_MipsRet : SDTypeProfile<0, 1, [SDTCisInt<0>]>;
def MipsRet : SDNode<"MipsISD::Ret", SDT_MipsRet, [SDNPHasChain,
@ -46,12 +49,22 @@ def callseq_start : SDNode<"ISD::CALLSEQ_START", SDT_MipsCallSeq,
def callseq_end : SDNode<"ISD::CALLSEQ_END", SDT_MipsCallSeq,
[SDNPHasChain, SDNPOutFlag]>;
//===----------------------------------------------------------------------===//
// Mips Instruction Predicate Definitions.
//===----------------------------------------------------------------------===//
def IsStatic : Predicate<"TM.getRelocationModel() == Reloc::Static">;
//===----------------------------------------------------------------------===//
// Mips Operand, Complex Patterns and Transformations Definitions.
//===----------------------------------------------------------------------===//
// Instruction operand types
def brtarget : Operand<OtherVT>;
def calltarget : Operand<i32>;
def uimm16 : Operand<i32>;
def simm16 : Operand<i32>;
def shamt : Operand<i32>;
def addrlabel : Operand<i32>;
// Address operand
def mem : Operand<i32> {
@ -59,10 +72,6 @@ def mem : Operand<i32> {
let MIOperandInfo = (ops simm16, CPURegs);
}
//===----------------------------------------------------------------------===//
// Mips Patterns and Transformations
//===----------------------------------------------------------------------===//
// Transformation Function - get the lower 16 bits.
def LO16 : SDNodeXForm<imm, [{
return getI32Imm((unsigned)N->getValue() & 0xFFFF);
@ -280,7 +289,7 @@ class JumpFR<bits<6> op, bits<6> func, string instr_asm>:
let isCall=1, hasDelaySlot=1,
// All calls clobber the non-callee saved registers...
Defs = [AT, V0, V1, A0, A1, A2, A3, T0, T1, T2,
T3, T4, T5, T6, T7, T8, T9, K0, K1, GP] in {
T3, T4, T5, T6, T7, T8, T9, K0, K1] in {
class JumpLink<bits<6> op, string instr_asm>:
FJ< op,
(outs),
@ -343,22 +352,34 @@ class EffectiveAddress<string instr_asm> :
// Pseudo instructions
//===----------------------------------------------------------------------===//
class Pseudo<dag outs, dag ins, string asmstr, list<dag> pattern>:
MipsInst<outs, ins, asmstr, pattern, IIPseudo>;
// As stack alignment is always done with addiu, we need a 16-bit immediate
let Defs = [SP], Uses = [SP] in {
def ADJCALLSTACKDOWN : Pseudo<(outs), (ins uimm16:$amt),
"!ADJCALLSTACKDOWN $amt",
[(callseq_start imm:$amt)]>;
def ADJCALLSTACKUP : Pseudo<(outs), (ins uimm16:$amt),
"!ADJCALLSTACKUP $amt",
[(callseq_end imm:$amt)]>;
def ADJCALLSTACKDOWN : PseudoInstMips<(outs), (ins uimm16:$amt),
"!ADJCALLSTACKDOWN $amt",
[(callseq_start imm:$amt)]>;
def ADJCALLSTACKUP : PseudoInstMips<(outs), (ins uimm16:$amt),
"!ADJCALLSTACKUP $amt",
[(callseq_end imm:$amt)]>;
}
def IMPLICIT_DEF_CPURegs : Pseudo<(outs CPURegs:$dst), (ins),
"!IMPLICIT_DEF $dst",
[(set CPURegs:$dst, (undef))]>;
def IMPLICIT_DEF_CPURegs : PseudoInstMips<(outs CPURegs:$dst), (ins),
"!IMPLICIT_DEF $dst",
[(set CPURegs:$dst, (undef))]>;
// When handling PIC code the assembler needs .cpload and .cprestore
// directives. If the real instructions corresponding these directives
// are used, we have the same behavior, but get also a bunch of warnings
// from the assembler.
def CPLOAD: PseudoInstMips<(outs), (ins CPURegs:$reg),
".set noreorder\n\t.cpload $reg\n\t.set reorder", []>;
def CPRESTORE: PseudoInstMips<(outs), (ins uimm16:$loc),
".cprestore $loc", []>;
// Used on PIC code only, it loads the address of label into register reg. The
// address is calculated from the global pointer ($gp) and is expanded by the
// assembler into two instructions "lw" and "addiu".
def LA: PseudoInstMips<(outs CPURegs:$dst), (ins addrlabel:$label),
"la $dst, $label", []>;
//===----------------------------------------------------------------------===//
// Instruction definition
@ -507,6 +528,7 @@ def : Pat<(MipsHi tglobaladdr:$in), (LUi tglobaladdr:$in)>;
def : Pat<(MipsLo tglobaladdr:$in), (ADDiu ZERO, tglobaladdr:$in)>;
def : Pat<(MipsAdd CPURegs:$hi, (MipsLo tglobaladdr:$lo)),
(ADDiu CPURegs:$hi, tglobaladdr:$lo)>;
def : Pat<(MipsLoadAddr tglobaladdr:$in), (LA tglobaladdr:$in)>;
// Mips does not have not, so we increase the operation
def : Pat<(not CPURegs:$in),