Files
Odin/core/rexcode/arm64/instructions.odin
Brendan Punsky 4cc6977321 Merge origin/bill/rexcode: struct repack (#raw_union #packed), wasm arch
Merge gingerBill's latest into bill/rexcode. His changes: minimize the
Instruction/Operand structs across ISAs with packed raw-unions (+ the
compiler support for #raw_union #packed), the new core:rexcode/wasm arch
and wasm/module, encode() now returns (byte_count, ok) instead of a Result
struct, decode_one made public, and assorted formatting/inlining.

Conflict: arm64/tests/pipeline_smoke.odin CSEL test -- kept the generated
4-arg inst_csel(dst,src,src2,cond) (mnemonic_builders.odin is generated,
not from Bill's branch) and adopted Bill's (byte_count, success) encode
signature.

Required rebuilding ./odin from the merged source for the packed-union
syntax. Re-validated after the repack: regenerated all artifacts
(idempotent -- no spurious churn), all 10 arches gen/builders/check/test
green, and byte-compared the new arm32 BF + mips PS/MMI/DSP/R6 forms to
confirm no field truncation. arm64/arm32/mips still 100%.
2026-06-18 05:44:48 -04:00

108 lines
4.3 KiB
Odin

// rexcode · Brendan Punsky (dotbmp@github), original author
package rexcode_arm64
// =============================================================================
// INSTRUCTION
// =============================================================================
Instruction_Flags :: bit_field u8 {
_: u8 | 8,
}
Instruction :: struct #packed {
ops: [4]Operand `fmt:"v,operand_count"`, // 4 * size_of(Operand)
mnemonic: Mnemonic, // 2
operand_count: u8, // 1
flags: Instruction_Flags, // 1
length: u8, // 1 -- always 4
_: [3]u8,
}
#assert(size_of(Instruction) == 64)
// =============================================================================
// Builders -- the most common shapes; less-common forms can be built
// inline by the caller using the Instruction struct directly.
// =============================================================================
@(require_results)
inst_none :: #force_inline proc "contextless" (m: Mnemonic) -> Instruction {
return Instruction{mnemonic = m, operand_count = 0, length = 4}
}
// Single-register (e.g. BR, BLR).
@(require_results)
inst_r :: #force_inline proc "contextless" (m: Mnemonic, r: Register) -> Instruction {
return Instruction{mnemonic = m, operand_count = 1, length = 4,
ops = {op_reg(r), {}, {}, {}}}
}
// 2-register (e.g. CLZ, RBIT).
@(require_results)
inst_r_r :: #force_inline proc "contextless" (m: Mnemonic, rd, rn: Register) -> Instruction {
return Instruction{mnemonic = m, operand_count = 2, length = 4,
ops = {op_reg(rd), op_reg(rn), {}, {}}}
}
// 3-register (e.g. ADD shifted, MUL, UDIV, ASRV).
@(require_results)
inst_r_r_r :: #force_inline proc "contextless" (m: Mnemonic, rd, rn, rm: Register) -> Instruction {
return Instruction{mnemonic = m, operand_count = 3, length = 4,
ops = {op_reg(rd), op_reg(rn), op_reg(rm), {}}}
}
// 4-register R4-type (MADD, MSUB, SMADDL, ...).
@(require_results)
inst_r_r_r_r :: #force_inline proc "contextless" (m: Mnemonic, rd, rn, rm, ra: Register) -> Instruction {
return Instruction{mnemonic = m, operand_count = 4, length = 4,
ops = {op_reg(rd), op_reg(rn), op_reg(rm), op_reg(ra)}}
}
// 2-register + immediate (e.g. ADD imm).
@(require_results)
inst_r_r_i :: #force_inline proc "contextless" (m: Mnemonic, rd, rn: Register, imm: i64) -> Instruction {
return Instruction{mnemonic = m, operand_count = 3, length = 4,
ops = {op_reg(rd), op_reg(rn), op_imm(imm), {}}}
}
// 1-register + immediate (e.g. MOVZ).
@(require_results)
inst_r_i :: #force_inline proc "contextless" (m: Mnemonic, rd: Register, imm: i64) -> Instruction {
return Instruction{mnemonic = m, operand_count = 2, length = 4,
ops = {op_reg(rd), op_imm(imm), {}, {}}}
}
// MOVZ/MOVN/MOVK with explicit hw shift (0/16/32/48).
@(require_results)
inst_mov_imm :: #force_inline proc "contextless" (m: Mnemonic, rd: Register, imm: i64, hw: u8) -> Instruction {
return Instruction{mnemonic = m, operand_count = 3, length = 4,
ops = {op_reg(rd), op_imm(imm), op_imm(i64(hw), 1), {}}}
}
// Load/store register: Rt + memory.
@(require_results)
inst_ldst :: #force_inline proc "contextless" (m: Mnemonic, rt: Register, mm: Memory) -> Instruction {
return Instruction{mnemonic = m, operand_count = 2, length = 4,
ops = {op_reg(rt), op_mem(mm), {}, {}}}
}
// Load/store pair: Rt, Rt2, memory.
@(require_results)
inst_ldp_stp :: #force_inline proc "contextless" (m: Mnemonic, rt, rt2: Register, mm: Memory) -> Instruction {
return Instruction{mnemonic = m, operand_count = 3, length = 4,
ops = {op_reg(rt), op_reg(rt2), op_mem(mm), {}}}
}
// PC-relative branch (B, BL).
@(require_results)
inst_branch :: #force_inline proc "contextless" (m: Mnemonic, label_id: u32) -> Instruction {
return Instruction{mnemonic = m, operand_count = 1, length = 4,
ops = {op_label(label_id, 4), {}, {}, {}}}
}
// NOTE: inst_b_cond / inst_cbz (+cbnz) / inst_tbz (+tbnz) /
// inst_csel (+csinc/csinv/csneg) are now generated per-mnemonic in
// mnemonic_builders.odin (e.g. inst_cbz(rt, label), inst_cbnz(rt, label),
// inst_csinc(rd, rn, rm, cond)). They are no longer hand-written here so the
// generator can own those names for full mnemonic coverage.