diff options
| author | Alexander Graf <agraf@suse.de> | 2015-05-08 03:06:41 +0200 |
|---|---|---|
| committer | Alexander Graf <agraf@suse.de> | 2015-05-13 14:48:54 +0200 |
| commit | 13f67dd5825a7dfd7a4904a5fb0cf0a3f95d2d45 (patch) | |
| tree | 846a633da07cd8dbb49d00397eb5317ccc7a587a /target-s390x | |
| parent | c095ed731ce4fecf166e4ac02ddc606b408f5e1f (diff) | |
s390x: Add some documentation in opcode list
I find it really hard to grasp what each field in the opcode list means.
Slowly walking through its semantics myself, I figured I'd write a small
summary at the top of the file to make life easier for me and whoever
looks at the file next.
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'target-s390x')
| -rw-r--r-- | target-s390x/insn-data.def | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/target-s390x/insn-data.def b/target-s390x/insn-data.def index 8d8e47e0bf..48e979e881 100644 --- a/target-s390x/insn-data.def +++ b/target-s390x/insn-data.def @@ -1,3 +1,24 @@ +/* + * Arguments to the opcode prototypes + * + * C(OPC, NAME, FMT, FAC, I1, I2, P, W, OP, CC) + * D(OPC, NAME, FMT, FAC, I1, I2, P, W, OP, CC, DATA) + * + * OPC = (op << 8) | op2 where op is the major, op2 the minor opcode + * NAME = name of the opcode, used internally + * FMT = format of the opcode (defined in insn-format.def) + * FAC = facility the opcode is available in (defined in DisasFacility) + * I1 = func in1_xx fills o->in1 + * I2 = func in2_xx fills o->in2 + * P = func prep_xx initializes o->*out* + * W = func wout_xx writes o->*out* somewhere + * OP = func op_xx does the bulk of the operation + * CC = func cout_xx defines how cc should get set + * DATA = immediate argument to op_xx function + * + * The helpers get called in order: I1, I2, P, OP, W, CC + */ + /* ADD */ C(0x1a00, AR, RR_a, Z, r1, r2, new, r1_32, add, adds32) C(0xb9f8, ARK, RRF_a, DO, r2, r3, new, r1_32, add, adds32) |