QEMU Developer Guide

--drive if=ide,media=cdrom,...

-netdev user,id=unet,hostfwd=tcp::8022-:22 -device virtio-net-device,netdev=unet

--cdrom filename

${QEMU} -serial mon:stdio ...
C-a c
(qemu)

mkdir -p builds/all && cd builds/all
../../configure

mkdir -p builds/arm.all && cd builds/arm.all
../../configure --disable-tools --disable-docs \
  --target-list=aarch64-softmmu,aarch64-linux-user,arm-softmmu,arm-linux-user

mkdir -p builds/all.debug && cd builds/all.debug
../../configure --enable-debug --extra-cflags="-O0 -g3"

mkdir -p builds/all.clang-sanitizer && cd builds/all.clang-sanitizer
../../configure --cc=clang-7 --cxx=clang++-7 \
  --enable-sanitizers \
  --target-list-exclude=xtensa-softmmu,xtensa-linux-user \
  --extra-cflags="-O0 -g3"

uint32_t insn = arm_ldl_code(env, s->base.pc_next, s->sctlr_b);
...
int rd = extract32(insn, 0, 5);
int rn = extract32(insn, 5, 5);
uint64_t imm = extract32(insn, 10, 12);
bool setflags = extract32(insn, 29, 1);
bool is_64bit = extract32(insn, 31, 1);

TCGv_i64 tcg_rn = cpu_reg(s, rn);
TCGv_i64 tcg_rd = setflags ? cpu_reg(s, rd) : cpu_reg_sp(s, rd);
TCGv_i64 tcg_result;

cpu_X[i] = tcg_global_mem_new_i64(cpu_env,
                                  offsetof(CPUARMState, xregs[i]),
                                  regnames[i]);
...
...
TCGv_i64 cpu_reg(DisasContext *s, int reg)
{
    if (reg == 31) {
        return new_tmp_a64_zero(s);
    } else {
        return cpu_X[reg];
    }
}

static TCGv_i64 read_fp_dreg(DisasContext *s, int reg)
{
    TCGv_i64 v = tcg_temp_new_i64();

    tcg_gen_ld_i64(v, cpu_env, fp_reg_offset(s, reg, MO_64));
    return v;
}

tcg_result = tcg_temp_new_i64();
tcg_gen_subi_i64(tcg_result, tcg_rn, imm);
if (is_64bit) {
    tcg_gen_mov_i64(tcg_rd, tcg_result);
} else {
    tcg_gen_ext32u_i64(tcg_rd, tcg_result);
}
tcg_temp_free_i64(tcg_result);

/* in helper.h */
DEF_HELPER_2(my_sub, i64, i64, i64)
/* in foo_helper.c */
uint64_t HELPER(my_sub)(uint64_t a, uint64_t b)
{
    return a - b;
}
/* in translate.c */
TCGv_i64 tcg_imm = tcg_const_i64(imm);
gen_helper_my_sub(tcg_rd, tcg_rn, tcg_imm);
tcg_temp_free_i64(tcg_imm);

${QEMU} -d in_asm,op,op_opt,out_asm [-s -S|-g] ${TESTCASE}

gdb-multiarch ${TESTCASE} -ex "target remote localhost:1234"

/usr/bin/qemu-system-ppc64le -name guest=debian-buster-ppc64le,debug-threads=on \
  -S \
  -object secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-12-debian-buster-ppc64l/master-key.aes \
  -machine pseries-2.12,accel=tcg,usb=off,dump-guest-core=off \
  -m 4096 -realtime mlock=off -smp 8,sockets=8,cores=1,threads=1 \
  -uuid a554f3b4-f59a-4879-a245-b5bf905aed0e \
  -no-user-config -nodefaults \
  -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-12-debian-buster-ppc64l/monitor.sock,server,nowait \
  -mon chardev=charmonitor,id=monitor,mode=control \
  -rtc base=utc \
  -no-shutdown -boot strict=on \
  -device qemu-xhci,p2=15,p3=15,id=usb,bus=pci.0,addr=0x3 \
  -device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x4 \
  -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x5 \
  -drive file=/dev/zvol/hackpool-0/debian-buster-ppc64el,format=raw,if=none,id=drive-virtio-disk0,cache=none,aio=native \
  -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x6,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 \
  -drive if=none,id=drive-scsi0-0-0-0,readonly=on \
  -device scsi-cd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0 \
  -netdev tap,fd=28,id=hostnet0 \
  -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:d9:0e:28,bus=pci.0,addr=0x1 \
  -chardev pty,id=charserial0 -device spapr-vty,chardev=charserial0,id=serial0,reg=0x30000000 \
  -chardev socket,id=charchannel0,path=/var/lib/libvirt/qemu/channel/target/domain-12-debian-buster-ppc64l/org.qemu.guest_agent.0,server,nowait \
  -device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0 \
  -chardev spicevmc,id=charchannel1,name=vdagent \
  -device virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0 \
  -device usb-kbd,id=input0,bus=usb.0,port=1 -device usb-mouse,id=input1,bus=usb.0,port=2 \
  -spice port=5900,addr=127.0.0.1,disable-ticketing,seamless-migration=on \
  -device VGA,id=video0,vgamem_mb=16,bus=pci.0,addr=0x9 \
  -device intel-hda,id=sound0,bus=pci.0,addr=0x2 \
  -device hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 \
  -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x7 \
  -object rng-random,id=objrng0,filename=/dev/urandom \
  -device virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.0,addr=0x8 \
  -msg timestamp=on

./ppc64-softmmu/qemu-system-ppc64 \
  -machine pseries-2.12 -m 4096 -smp 8 \
  -nodefaults \
  -serial mon:stdio \
  -no-shutdown -boot strict=on \
  -device virtio-scsi-pci,id=scsi0 
  -drive file=/dev/zvol/hackpool-0/debian-buster-ppc64el,format=raw,if=none,id=drive-virtio-disk0 \
  -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x6,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 \
  -drive if=none,id=drive-scsi0-0-0-0,readonly=on \
  -nic user,model=virtio-net-pci,hostfwd=tcp::2222-:22 \
  -display none