Enum Control 

pub enum Control {
    If {
        else_offset: usize,
        end_offset: usize,
    },
    Loop {
        count: u8,
        initial: u8,
        increment: u8,
        end_offset: usize,
    },
    Repeat {
        counts: [u8; 3],
        end_offset: usize,
    },
    Call {
        target: usize,
        encoded: [u32; 3],
    },
    Break,
    Return,
}

What a flow-control instruction does.

Variants

If

IFE: a conditional block.

Fields

else_offset: usize

The byte offset of the else block.

end_offset: usize

The byte offset where the block ends.

Loop

LOOP: the three byte fields of the second operand word are the count (bits 2 to 9), the initial counter value (10 to 17) and the increment (19 to 26), as RPCS3 and Mesa name them. No program on Tony Hawk’s SHRED disc uses it.

Fields

count: u8

The iteration count.

initial: u8

The initial counter value.

increment: u8

The counter increment.

end_offset: usize

The byte offset where the loop ends (the third operand word without its top bit).

Repeat

REP: the same three byte fields, which Mesa found always filled with one value (a repeat count) and names count1, count2 and count3; RPCS3 reads the first as the repeat count. Kept as stored, in that order.

Fields

counts: [u8; 3]

The three counts as stored (bits 2 to 9, 10 to 17 and 19 to 26 of the second operand word).

end_offset: usize

The byte offset where the repeated block ends.

Call

CAL: a subroutine call. The target is the second operand word without its top bit, a count of 32-bit words as every other branch offset is (Mesa’s NV40_FP_OP_SUB_OFFSET); it must be an instruction boundary.

Fields

target: usize

The byte offset of the first instruction of the subroutine.

encoded: [u32; 3]

The instruction’s three operand words, as stored.

Break

BRK.

Return

RET.

Trait Implementations

impl Clone for Control

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Control

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Control

impl PartialEq for Control

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Control