darling-JavaScriptCore/offlineasm/arm.rb

732 lines
26 KiB
Ruby

# Copyright (C) 2011-2020 Apple Inc. All rights reserved.
# Copyright (C) 2013 University of Szeged. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
# THE POSSIBILITY OF SUCH DAMAGE.
require "config"
require "ast"
require "opt"
require "risc"
# GPR conventions, to match the baseline JIT
#
# x0 => t0, a0, r0
# x1 => t1, a1, r1
# x2 => t2, a2, r2
# x3 => t3, a3, r3
# x6 => (callee-save scratch)
# x7 => cfr
# x8 => t4 (callee-save)
# x9 => t5 (callee-save)
# x10 => csr1 (callee-save, PB)
# x11 => cfr, csr0 (callee-save, metadataTable)
# x12 => (callee-save scratch)
# lr => lr
# sp => sp
# pc => pc
#
# FPR conventions, to match the baseline JIT
#
# d0 => ft0, fa0, fr
# d1 => ft1, fa1
# d2 => ft2
# d3 => ft3
# d4 => ft4
# d5 => ft5
# d6 => (scratch)
# d7 => (scratch)
class Node
def armSingle
doubleOperand = armOperand
raise "Bogus register name #{doubleOperand}" unless doubleOperand =~ /^d/
"s" + ($~.post_match.to_i * 2).to_s
end
end
class SpecialRegister
def armOperand
@name
end
end
ARM_EXTRA_GPRS = [SpecialRegister.new("r6"), SpecialRegister.new("r4"), SpecialRegister.new("r12")]
ARM_EXTRA_FPRS = [SpecialRegister.new("d7")]
ARM_SCRATCH_FPR = SpecialRegister.new("d6")
OS_DARWIN = ((RUBY_PLATFORM =~ /darwin/i) != nil)
def armMoveImmediate(value, register)
# Currently we only handle the simple cases, and fall back to mov/movt for the complex ones.
if value.is_a? String
$asm.puts "mov #{register.armOperand}, (#{value})"
elsif value >= 0 && value < 256
$asm.puts "mov #{register.armOperand}, \##{value}"
elsif (~value) >= 0 && (~value) < 256
$asm.puts "mvn #{register.armOperand}, \##{~value}"
else
$asm.puts "movw #{register.armOperand}, \##{value & 0xffff}"
if (value & 0xffff0000) != 0
$asm.puts "movt #{register.armOperand}, \##{(value >> 16) & 0xffff}"
end
end
end
class RegisterID
def armOperand
case name
when "t0", "a0", "r0"
"r0"
when "t1", "a1", "r1"
"r1"
when "t2", "a2"
"r2"
when "a3"
"r3"
when "t3"
"r3"
when "t4"
"r8"
when "t5"
"r9"
when "cfr"
"r7"
when "csr0"
"r11"
when "csr1"
"r10"
when "lr"
"lr"
when "sp"
"sp"
when "pc"
"pc"
else
raise "Bad register #{name} for ARM at #{codeOriginString}"
end
end
end
class FPRegisterID
def armOperand
case name
when "ft0", "fr", "fa0"
"d0"
when "ft1", "fa1"
"d1"
when "ft2"
"d2"
when "ft3"
"d3"
when "ft4"
"d4"
when "ft5"
"d5"
else
raise "Bad register #{name} for ARM at #{codeOriginString}"
end
end
end
class Immediate
def armOperand
raise "Invalid immediate #{value} at #{codeOriginString}" if value < 0 or value > 255
"\##{value}"
end
end
class Address
def armOperand
raise "Bad offset at #{codeOriginString}" if offset.value < -0xff or offset.value > 0xfff
"[#{base.armOperand}, \##{offset.value}]"
end
end
class BaseIndex
def armOperand
raise "Bad offset at #{codeOriginString}" if offset.value != 0
"[#{base.armOperand}, #{index.armOperand}, lsl \##{scaleShift}]"
end
end
class AbsoluteAddress
def armOperand
raise "Unconverted absolute address at #{codeOriginString}"
end
end
#
# Lea support.
#
class Address
def armEmitLea(destination)
if destination == base
$asm.puts "adds #{destination.armOperand}, \##{offset.value}"
else
$asm.puts "adds #{destination.armOperand}, #{base.armOperand}, \##{offset.value}"
end
end
end
class BaseIndex
def armEmitLea(destination)
raise "Malformed BaseIndex, offset should be zero at #{codeOriginString}" unless offset.value == 0
$asm.puts "add #{destination.armOperand}, #{base.armOperand}, #{index.armOperand}, lsl \##{scaleShift}"
end
end
# FIXME: we could support AbsoluteAddress for lea, but we don't.
#
# Actual lowering code follows.
#
def armOpcodeReversedOperands(opcode)
m = /\Ab[ipb]/.match(opcode)
operation =
case m.post_match
when "eq" then "eq"
when "neq" then "neq"
when "a" then "b"
when "aeq" then "beq"
when "b" then "a"
when "beq" then "aeq"
when "gt" then "lt"
when "gteq" then "lteq"
when "lt" then "gt"
when "lteq" then "gteq"
else
raise "unknown operation #{m.post_match}"
end
"#{m[0]}#{operation}"
end
def armLowerStackPointerInComparison(list)
newList = []
list.each {
| node |
if node.is_a? Instruction
case node.opcode
when "bieq", "bpeq", "bbeq",
"bineq", "bpneq", "bbneq",
"bia", "bpa", "bba",
"biaeq", "bpaeq", "bbaeq",
"bib", "bpb", "bbb",
"bibeq", "bpbeq", "bbbeq",
"bigt", "bpgt", "bbgt",
"bigteq", "bpgteq", "bbgteq",
"bilt", "bplt", "bblt",
"bilteq", "bplteq", "bblteq"
if node.operands[1].is_a?(RegisterID) && node.operands[1].name == "sp"
newList << Instruction.new(codeOrigin, armOpcodeReversedOperands(node.opcode), [node.operands[1], node.operands[0]] + node.operands[2..-1])
else
newList << node
end
else
newList << node
end
else
newList << node
end
}
newList
end
def armLowerLabelReferences(list)
newList = []
list.each {
| node |
if node.is_a? Instruction
case node.opcode
when "leai", "leap", "leaq"
labelRef = node.operands[0]
if labelRef.is_a? LabelReference
tmp = Tmp.new(node.codeOrigin, :gpr)
newList << Instruction.new(codeOrigin, "globaladdr", [LabelReference.new(node.codeOrigin, labelRef.label), node.operands[1], tmp])
# FIXME: This check against 255 is just the simplest check we can do. ARM is capable of encoding some larger constants using
# rotation (subject to some special rules). Perhaps we can add the more comprehensive encoding check here.
if labelRef.offset > 255
newList << Instruction.new(codeOrigin, "move", [Immediate.new(node.codeOrigin, labelRef.offset), tmp])
newList << Instruction.new(codeOrigin, "addp", [tmp, node.operands[1]])
elsif labelRef.offset > 0
newList << Instruction.new(codeOrigin, "addp", [Immediate.new(node.codeOrigin, labelRef.offset), node.operands[1]])
end
else
newList << node
end
else
newList << node
end
else
newList << node
end
}
newList
end
class Sequence
def getModifiedListARMv7
raise unless $activeBackend == "ARMv7"
getModifiedListARMCommon
end
def getModifiedListARMCommon
result = @list
result = riscLowerSimpleBranchOps(result)
result = riscLowerHardBranchOps(result)
result = riscLowerShiftOps(result)
result = armLowerLabelReferences(result)
result = riscLowerMalformedAddresses(result) {
| node, address |
if address.is_a? BaseIndex
address.offset.value == 0
elsif address.is_a? Address
(-0xff..0xfff).include? address.offset.value
else
false
end
}
result = riscLowerMalformedAddressesDouble(result)
result = riscLowerMisplacedImmediates(result, ["storeb", "storeh", "storei", "storep", "storeq"])
result = riscLowerMalformedImmediates(result, 0..0xff, 0..0x0ff)
result = riscLowerMisplacedAddresses(result)
result = riscLowerRegisterReuse(result)
result = assignRegistersToTemporaries(result, :gpr, ARM_EXTRA_GPRS)
result = assignRegistersToTemporaries(result, :fpr, ARM_EXTRA_FPRS)
result = armLowerStackPointerInComparison(result)
return result
end
end
def armOperands(operands)
operands.map{|v| v.armOperand}.join(", ")
end
def armFlippedOperands(operands)
armOperands([operands[-1]] + operands[0..-2])
end
def emitArmCompact(opcode2, opcode3, operands)
if operands.size == 3
$asm.puts "#{opcode3} #{armFlippedOperands(operands)}"
else
raise unless operands.size == 2
raise unless operands[1].register?
if operands[0].immediate?
$asm.puts "#{opcode3} #{operands[1].armOperand}, #{operands[1].armOperand}, #{operands[0].armOperand}"
else
$asm.puts "#{opcode2} #{armFlippedOperands(operands)}"
end
end
end
def emitArm(opcode, operands)
if operands.size == 3
$asm.puts "#{opcode} #{armFlippedOperands(operands)}"
else
raise unless operands.size == 2
$asm.puts "#{opcode} #{operands[1].armOperand}, #{operands[1].armOperand}, #{operands[0].armOperand}"
end
end
def emitArmDoubleBranch(branchOpcode, operands)
$asm.puts "vcmpe.f64 #{armOperands(operands[0..1])}"
$asm.puts "vmrs apsr_nzcv, fpscr"
$asm.puts "#{branchOpcode} #{operands[2].asmLabel}"
end
def emitArmTest(operands)
value = operands[0]
case operands.size
when 2
mask = Immediate.new(codeOrigin, -1)
when 3
mask = operands[1]
else
raise "Expected 2 or 3 operands but got #{operands.size} at #{codeOriginString}"
end
if mask.immediate? and mask.value == -1
$asm.puts "tst #{value.armOperand}, #{value.armOperand}"
else
$asm.puts "tst #{value.armOperand}, #{mask.armOperand}"
end
end
def emitArmCompare(operands, code)
$asm.puts "movs #{operands[2].armOperand}, \#0"
$asm.puts "cmp #{operands[0].armOperand}, #{operands[1].armOperand}"
$asm.puts "it #{code}"
$asm.puts "mov#{code} #{operands[2].armOperand}, \#1"
end
def emitArmTestSet(operands, code)
$asm.puts "movs #{operands[-1].armOperand}, \#0"
emitArmTest(operands)
$asm.puts "it #{code}"
$asm.puts "mov#{code} #{operands[-1].armOperand}, \#1"
end
class Instruction
def lowerARMv7
raise unless $activeBackend == "ARMv7"
lowerARMCommon
end
def lowerARMCommon
case opcode
when "addi", "addp", "addis", "addps"
if opcode == "addis" or opcode == "addps"
suffix = "s"
else
suffix = ""
end
if operands.size == 3 and operands[0].immediate?
raise unless operands[1].register?
raise unless operands[2].register?
if operands[0].value == 0 and suffix.empty?
unless operands[1] == operands[2]
$asm.puts "mov #{operands[2].armOperand}, #{operands[1].armOperand}"
end
else
$asm.puts "adds #{operands[2].armOperand}, #{operands[1].armOperand}, #{operands[0].armOperand}"
end
elsif operands.size == 3 and operands[0].register?
raise unless operands[1].register?
raise unless operands[2].register?
$asm.puts "adds #{armFlippedOperands(operands)}"
else
if operands[0].immediate?
unless Immediate.new(nil, 0) == operands[0]
$asm.puts "adds #{armFlippedOperands(operands)}"
end
else
$asm.puts "add#{suffix} #{armFlippedOperands(operands)}"
end
end
when "andi", "andp"
emitArmCompact("ands", "and", operands)
when "ori", "orp", "orh"
emitArmCompact("orrs", "orr", operands)
when "oris"
emitArmCompact("orrs", "orrs", operands)
when "xori", "xorp"
emitArmCompact("eors", "eor", operands)
when "lshifti", "lshiftp"
emitArmCompact("lsls", "lsls", operands)
when "rshifti", "rshiftp"
emitArmCompact("asrs", "asrs", operands)
when "urshifti", "urshiftp"
emitArmCompact("lsrs", "lsrs", operands)
when "muli", "mulp"
emitArm("mul", operands)
when "subi", "subp", "subis"
emitArmCompact("subs", "subs", operands)
when "negi", "negp"
$asm.puts "rsbs #{operands[0].armOperand}, #{operands[0].armOperand}, \#0"
when "noti"
$asm.puts "mvns #{operands[0].armOperand}, #{operands[0].armOperand}"
when "loadi", "loadis", "loadp"
$asm.puts "ldr #{armFlippedOperands(operands)}"
when "storei", "storep"
$asm.puts "str #{armOperands(operands)}"
when "loadb"
$asm.puts "ldrb #{armFlippedOperands(operands)}"
when "loadbsi"
$asm.puts "ldrsb.w #{armFlippedOperands(operands)}"
when "storeb"
$asm.puts "strb #{armOperands(operands)}"
when "loadh"
$asm.puts "ldrh #{armFlippedOperands(operands)}"
when "loadhsi"
$asm.puts "ldrsh.w #{armFlippedOperands(operands)}"
when "storeh"
$asm.puts "strh #{armOperands(operands)}"
when "loadd"
$asm.puts "vldr.64 #{armFlippedOperands(operands)}"
when "stored"
$asm.puts "vstr.64 #{armOperands(operands)}"
when "addd"
emitArm("vadd.f64", operands)
when "divd"
emitArm("vdiv.f64", operands)
when "subd"
emitArm("vsub.f64", operands)
when "muld"
emitArm("vmul.f64", operands)
when "sqrtd"
$asm.puts "vsqrt.f64 #{armFlippedOperands(operands)}"
when "ci2ds"
$asm.puts "vmov #{operands[1].armSingle}, #{operands[0].armOperand}"
$asm.puts "vcvt.f64.s32 #{operands[1].armOperand}, #{operands[1].armSingle}"
when "bdeq"
emitArmDoubleBranch("beq", operands)
when "bdneq"
$asm.puts "vcmpe.f64 #{armOperands(operands[0..1])}"
$asm.puts "vmrs apsr_nzcv, fpscr"
isUnordered = LocalLabel.unique("bdneq")
$asm.puts "bvs #{LocalLabelReference.new(codeOrigin, isUnordered).asmLabel}"
$asm.puts "bne #{operands[2].asmLabel}"
isUnordered.lower("ARM")
when "bdgt"
emitArmDoubleBranch("bgt", operands)
when "bdgteq"
emitArmDoubleBranch("bge", operands)
when "bdlt"
emitArmDoubleBranch("bmi", operands)
when "bdlteq"
emitArmDoubleBranch("bls", operands)
when "bdequn"
$asm.puts "vcmpe.f64 #{armOperands(operands[0..1])}"
$asm.puts "vmrs apsr_nzcv, fpscr"
$asm.puts "bvs #{operands[2].asmLabel}"
$asm.puts "beq #{operands[2].asmLabel}"
when "bdnequn"
emitArmDoubleBranch("bne", operands)
when "bdgtun"
emitArmDoubleBranch("bhi", operands)
when "bdgtequn"
emitArmDoubleBranch("bpl", operands)
when "bdltun"
emitArmDoubleBranch("blt", operands)
when "bdltequn"
emitArmDoubleBranch("ble", operands)
when "btd2i"
# FIXME: may be a good idea to just get rid of this instruction, since the interpreter
# currently does not use it.
raise "ARM does not support this opcode yet, #{codeOrigin}"
when "td2i"
$asm.puts "vcvt.s32.f64 #{ARM_SCRATCH_FPR.armSingle}, #{operands[0].armOperand}"
$asm.puts "vmov #{operands[1].armOperand}, #{ARM_SCRATCH_FPR.armSingle}"
when "bcd2i"
$asm.puts "vcvt.s32.f64 #{ARM_SCRATCH_FPR.armSingle}, #{operands[0].armOperand}"
$asm.puts "vmov #{operands[1].armOperand}, #{ARM_SCRATCH_FPR.armSingle}"
$asm.puts "vcvt.f64.s32 #{ARM_SCRATCH_FPR.armOperand}, #{ARM_SCRATCH_FPR.armSingle}"
emitArmDoubleBranch("bne", [ARM_SCRATCH_FPR, operands[0], operands[2]])
$asm.puts "tst #{operands[1].armOperand}, #{operands[1].armOperand}"
$asm.puts "beq #{operands[2].asmLabel}"
when "movdz"
# FIXME: either support this or remove it.
raise "ARM does not support this opcode yet, #{codeOrigin}"
when "pop"
operands.each {
| op |
$asm.puts "pop { #{op.armOperand} }"
}
when "push"
operands.each {
| op |
$asm.puts "push { #{op.armOperand} }"
}
when "move"
if operands[0].immediate?
armMoveImmediate(operands[0].value, operands[1])
else
$asm.puts "mov #{armFlippedOperands(operands)}"
end
when "mvlbl"
$asm.puts "movw #{operands[1].armOperand}, \#:lower16:#{operands[0].value}"
$asm.puts "movt #{operands[1].armOperand}, \#:upper16:#{operands[0].value}"
when "nop"
$asm.puts "nop"
when "bieq", "bpeq", "bbeq"
if Immediate.new(nil, 0) == operands[0]
$asm.puts "tst #{operands[1].armOperand}, #{operands[1].armOperand}"
elsif Immediate.new(nil, 0) == operands[1]
$asm.puts "tst #{operands[0].armOperand}, #{operands[0].armOperand}"
else
$asm.puts "cmp #{armOperands(operands[0..1])}"
end
$asm.puts "beq #{operands[2].asmLabel}"
when "bineq", "bpneq", "bbneq"
if Immediate.new(nil, 0) == operands[0]
$asm.puts "tst #{operands[1].armOperand}, #{operands[1].armOperand}"
elsif Immediate.new(nil, 0) == operands[1]
$asm.puts "tst #{operands[0].armOperand}, #{operands[0].armOperand}"
else
$asm.puts "cmp #{armOperands(operands[0..1])}"
end
$asm.puts "bne #{operands[2].asmLabel}"
when "bia", "bpa", "bba"
$asm.puts "cmp #{armOperands(operands[0..1])}"
$asm.puts "bhi #{operands[2].asmLabel}"
when "biaeq", "bpaeq", "bbaeq"
$asm.puts "cmp #{armOperands(operands[0..1])}"
$asm.puts "bhs #{operands[2].asmLabel}"
when "bib", "bpb", "bbb"
$asm.puts "cmp #{armOperands(operands[0..1])}"
$asm.puts "blo #{operands[2].asmLabel}"
when "bibeq", "bpbeq", "bbbeq"
$asm.puts "cmp #{armOperands(operands[0..1])}"
$asm.puts "bls #{operands[2].asmLabel}"
when "bigt", "bpgt", "bbgt"
$asm.puts "cmp #{armOperands(operands[0..1])}"
$asm.puts "bgt #{operands[2].asmLabel}"
when "bigteq", "bpgteq", "bbgteq"
$asm.puts "cmp #{armOperands(operands[0..1])}"
$asm.puts "bge #{operands[2].asmLabel}"
when "bilt", "bplt", "bblt"
$asm.puts "cmp #{armOperands(operands[0..1])}"
$asm.puts "blt #{operands[2].asmLabel}"
when "bilteq", "bplteq", "bblteq"
$asm.puts "cmp #{armOperands(operands[0..1])}"
$asm.puts "ble #{operands[2].asmLabel}"
when "btiz", "btpz", "btbz"
emitArmTest(operands)
$asm.puts "beq #{operands[-1].asmLabel}"
when "btinz", "btpnz", "btbnz"
emitArmTest(operands)
$asm.puts "bne #{operands[-1].asmLabel}"
when "btis", "btps", "btbs"
emitArmTest(operands)
$asm.puts "bmi #{operands[-1].asmLabel}"
when "jmp"
if operands[0].label?
$asm.puts "b #{operands[0].asmLabel}"
else
$asm.puts "mov pc, #{operands[0].armOperand}"
end
when "call"
if operands[0].label?
if OS_DARWIN
$asm.puts "blx #{operands[0].asmLabel}"
else
$asm.puts "bl #{operands[0].asmLabel}"
end
else
$asm.puts "blx #{operands[0].armOperand}"
end
when "break"
$asm.puts "bkpt #0"
when "ret"
$asm.puts "bx lr"
when "cieq", "cpeq", "cbeq"
emitArmCompare(operands, "eq")
when "cineq", "cpneq", "cbneq"
emitArmCompare(operands, "ne")
when "cia", "cpa", "cba"
emitArmCompare(operands, "hi")
when "ciaeq", "cpaeq", "cbaeq"
emitArmCompare(operands, "hs")
when "cib", "cpb", "cbb"
emitArmCompare(operands, "lo")
when "cibeq", "cpbeq", "cbbeq"
emitArmCompare(operands, "ls")
when "cigt", "cpgt", "cbgt"
emitArmCompare(operands, "gt")
when "cigteq", "cpgteq", "cbgteq"
emitArmCompare(operands, "ge")
when "cilt", "cplt", "cblt"
emitArmCompare(operands, "lt")
when "cilteq", "cplteq", "cblteq"
emitArmCompare(operands, "le")
when "tis", "tbs", "tps"
emitArmTestSet(operands, "mi")
when "tiz", "tbz", "tpz"
emitArmTestSet(operands, "eq")
when "tinz", "tbnz", "tpnz"
emitArmTestSet(operands, "ne")
when "peek"
$asm.puts "ldr #{operands[1].armOperand}, [sp, \##{operands[0].value * 4}]"
when "poke"
$asm.puts "str #{operands[1].armOperand}, [sp, \##{operands[0].value * 4}]"
when "fii2d"
$asm.puts "vmov #{operands[2].armOperand}, #{operands[0].armOperand}, #{operands[1].armOperand}"
when "fd2ii"
$asm.puts "vmov #{operands[1].armOperand}, #{operands[2].armOperand}, #{operands[0].armOperand}"
when "bo"
$asm.puts "bvs #{operands[0].asmLabel}"
when "bs"
$asm.puts "bmi #{operands[0].asmLabel}"
when "bz"
$asm.puts "beq #{operands[0].asmLabel}"
when "bnz"
$asm.puts "bne #{operands[0].asmLabel}"
when "leai", "leap"
operands[0].armEmitLea(operands[1])
when "smulli"
raise "Wrong number of arguments to smull in #{self.inspect} at #{codeOriginString}" unless operands.length == 4
$asm.puts "smull #{operands[2].armOperand}, #{operands[3].armOperand}, #{operands[0].armOperand}, #{operands[1].armOperand}"
when "memfence"
$asm.puts "dmb sy"
when "clrbp"
$asm.puts "bic #{operands[2].armOperand}, #{operands[0].armOperand}, #{operands[1].armOperand}"
when "globaladdr"
labelRef = operands[0]
dest = operands[1]
temp = operands[2]
uid = $asm.newUID
$asm.putStr("#if OS(DARWIN)")
$asm.puts "movw #{operands[1].armOperand}, :lower16:(L#{operands[0].asmLabel}_#{uid}$non_lazy_ptr-(L_offlineasm_#{uid}+4))"
$asm.puts "movt #{operands[1].armOperand}, :upper16:(L#{operands[0].asmLabel}_#{uid}$non_lazy_ptr-(L_offlineasm_#{uid}+4))"
$asm.puts "L_offlineasm_#{uid}:"
$asm.puts "add #{operands[1].armOperand}, pc"
$asm.puts "ldr #{operands[1].armOperand}, [#{operands[1].armOperand}]"
# On Linux, use ELF GOT relocation specifiers.
$asm.putStr("#elif OS(LINUX)")
gotLabel = Assembler.localLabelReference("offlineasm_arm_got_#{uid}")
offsetLabel = Assembler.localLabelReference("offlineasm_arm_got_offset_#{uid}")
$asm.puts "ldr #{dest.armOperand}, #{gotLabel}"
$asm.puts "ldr #{temp.armOperand}, #{gotLabel}+4"
$asm.puts "#{offsetLabel}:"
$asm.puts "add #{dest.armOperand}, pc, #{dest.armOperand}"
$asm.puts "ldr #{dest.armOperand}, [#{dest.armOperand}, #{temp.armOperand}]"
# Throw a compiler error everywhere else.
$asm.putStr("#else")
$asm.putStr("#error Missing globaladdr implementation")
$asm.putStr("#endif")
offset = 4
$asm.deferNextLabelAction {
$asm.putStr("#if OS(DARWIN)")
$asm.puts ".section __DATA,__nl_symbol_ptr,non_lazy_symbol_pointers"
$asm.puts ".p2align 2"
$asm.puts "L#{operands[0].asmLabel}_#{uid}$non_lazy_ptr:"
$asm.puts ".indirect_symbol #{operands[0].asmLabel}"
$asm.puts ".long 0"
$asm.puts ".text"
$asm.puts ".align 4"
$asm.putStr("#elif OS(LINUX)")
$asm.puts "#{gotLabel}:"
$asm.puts ".word _GLOBAL_OFFSET_TABLE_-(#{offsetLabel}+#{offset})"
$asm.puts ".word #{labelRef.asmLabel}(GOT)"
$asm.putStr("#endif")
}
else
lowerDefault
end
end
end