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use super::*;
use crate::native::{emit, jit_mem::JitCode, mir_legalize, regalloc};
#[test]
fn indexed_dead_stores_preserve_intervening_observers() {
for size in [OpSize::S8, OpSize::S16, OpSize::S32, OpSize::S64] {
for bounded in [false, true] {
for effect in 0..12 {
let mut vregs = VRegAllocator::new();
for _ in 0..6 {
vregs.alloc();
}
let mut function = MFunction::new(vregs, vec![SpillDesc::transient(); 6]);
let mut block = MBlock::new(BlockId(0));
for (dst, offset) in [(VReg(0), 0), (VReg(1), 8), (VReg(2), 16)] {
block.push(MInst::Load {
dst,
base: BaseReg::SimState,
offset,
size: OpSize::S64,
});
}
block.push(MInst::LoadImm {
dst: VReg(3),
value: 0,
});
let envelope = bounded.then(|| MemoryAliasRange::new(64, 32).unwrap());
block.push(MInst::StoreIndexed {
base: BaseReg::SimState,
offset: 64,
index: VReg(1),
src: VReg(0),
size,
alias_range: if effect == 11 {
MemoryAliasRange::new(64, 40)
} else {
envelope
},
});
match effect {
1 | 2 => block.push(MInst::Load {
dst: VReg(4),
base: BaseReg::SimState,
offset: if effect == 1 { 96 } else { 64 },
size: OpSize::S64,
}),
3..=5 => block.push(MInst::LoadIndexed {
dst: VReg(4),
base: BaseReg::SimState,
offset: if effect == 3 { 96 } else { 64 },
index: VReg(1),
scale: 1,
size,
alias_range: match effect {
3 => MemoryAliasRange::new(96, 32),
4 => envelope,
_ => None,
},
}),
6 => block.push(MInst::OrStoreIndexed {
base: BaseReg::SimState,
offset: 64,
index: VReg(1),
src: VReg(0),
size,
alias_range: envelope,
}),
7 => block.push(MInst::MemCopy {
dst_offset: 128,
src_offset: 64,
byte_len: 32,
}),
8 => block.push(MInst::MemFill {
dst_offset: 64,
byte_len: 32,
value: 0xa5,
}),
_ => {}
}
if (1..=5).contains(&effect) {
block.push(MInst::Store {
base: BaseReg::SimState,
offset: 32,
src: VReg(4),
size: OpSize::S64,
});
}
block.push(MInst::StoreIndexed {
base: BaseReg::SimState,
offset: 64,
index: if effect == 9 { VReg(2) } else { VReg(1) },
src: VReg(3),
size: if effect == 10 && size != OpSize::S8 {
OpSize::S8
} else {
size
},
alias_range: envelope,
});
block.push(MInst::Return);
function.push_block(block);
let mut optimized = function.clone();
eliminate_redundant_local_stores(&mut optimized);
dead_code_eliminate(&mut optimized);
optimized.verify();
let removed = matches!(effect, 0 | 8)
|| bounded && matches!(effect, 1 | 3)
|| effect == 10 && size == OpSize::S8;
assert_eq!(
optimized.blocks[0]
.insts
.iter()
.filter(|inst| matches!(inst, MInst::StoreIndexed { .. }))
.count(),
if removed { 1 } else { 2 },
"size={size:?} bounded={bounded} effect={effect}"
);
let compile = |mut function: MFunction| {
mir_legalize::legalize(&mut function);
let allocation = regalloc::run_regalloc(&mut function).unwrap();
let emitted = emit::emit(
&function,
&allocation.assignment,
allocation.spill_frame_size,
)
.unwrap();
(
JitCode::new(&emitted.code).unwrap(),
emitted.required_state_size.max(160) as usize,
)
};
let (before, before_size) = compile(function);
let (after, after_size) = compile(optimized);
for input in [0u64, 1, 0x0123_4567_89ab_cdef, u64::MAX] {
for index in [0u64, 1, 8, 16] {
let mut left = vec![0x69u8; before_size.max(after_size)];
left[..8].copy_from_slice(&input.to_le_bytes());
left[8..16].copy_from_slice(&index.to_le_bytes());
left[16..24].copy_from_slice(&(16 - index).to_le_bytes());
let mut right = left.clone();
assert_eq!(unsafe { before.call(&mut left) }, 0);
assert_eq!(unsafe { after.call(&mut right) }, 0);
assert_eq!(
&left[..160],
&right[..160],
"size={size:?} bounded={bounded} effect={effect} input={input:#x} index={index}"
);
}
}
}
}
}
}
#[test]
fn live_partial_forwarding_preserves_bytes_across_widths_and_aliases() {
for wide in [OpSize::S16, OpSize::S32, OpSize::S64] {
for narrow in [OpSize::S8, OpSize::S16, OpSize::S32] {
if narrow.bytes() >= wide.bytes() {
continue;
}
for displacement in 0..=wide.bytes() - narrow.bytes() {
for effect in 0..5 {
let mut vregs = VRegAllocator::new();
for _ in 0..5 {
vregs.alloc();
}
let mut function = MFunction::new(vregs, vec![SpillDesc::transient(); 5]);
let mut block = MBlock::new(BlockId(0));
block.push(MInst::Load {
dst: VReg(0),
base: BaseReg::SimState,
offset: 0,
size: OpSize::S64,
});
block.push(MInst::LoadImm {
dst: VReg(1),
value: 0,
});
block.push(MInst::Store {
base: BaseReg::SimState,
offset: 64 + displacement as i32,
src: VReg(0),
size: narrow,
});
// Reading the bytes before the final observation must not
// make a forwarded store disappear from observable state.
block.push(MInst::Load {
dst: VReg(2),
base: BaseReg::SimState,
offset: 64,
size: wide,
});
let (offset, alias_range) = match effect {
1 | 4 => (80, MemoryAliasRange::new(80, 8)),
_ => (64, None),
};
match effect {
1 | 2 => block.push(MInst::MemFill {
dst_offset: offset,
byte_len: 1,
value: 0xa5,
}),
3 | 4 => block.push(MInst::StoreIndexed {
base: BaseReg::SimState,
offset,
index: VReg(1),
src: VReg(0),
size: OpSize::S8,
alias_range,
}),
_ => {}
}
block.push(MInst::Load {
dst: VReg(3),
base: BaseReg::SimState,
offset: 64,
size: wide,
});
for (source, offset) in [(VReg(2), 16), (VReg(3), 24)] {
block.push(MInst::Store {
base: BaseReg::SimState,
offset,
src: source,
size: OpSize::S64,
});
}
block.push(MInst::Return);
function.push_block(block);
forward_live_partial_stores(&mut function);
known_bits::fold(&mut function);
for _ in 0..2 {
known_bits::fold_demanded(&mut function);
algebraic_simplify(&mut function);
copy_propagate(&mut function);
dead_code_eliminate(&mut function);
}
function.verify();
mir_legalize::legalize(&mut function);
let allocation = regalloc::run_regalloc(&mut function).unwrap();
let emitted = emit::emit(
&function,
&allocation.assignment,
allocation.spill_frame_size,
)
.unwrap();
let jit = JitCode::new(&emitted.code).unwrap();
for input in [0u64, 1, 0x0123_4567_89ab_cdef, u64::MAX] {
let mut state = vec![0x69u8; emitted.required_state_size.max(96) as usize];
state[..8].copy_from_slice(&input.to_le_bytes());
let mut expected = state.clone();
let start = 64 + displacement as usize;
expected[start..start + narrow.bytes() as usize]
.copy_from_slice(&input.to_le_bytes()[..narrow.bytes() as usize]);
let observed = |state: &[u8]| {
let mut bytes = [0u8; 8];
bytes[..wide.bytes() as usize]
.copy_from_slice(&state[64..64 + wide.bytes() as usize]);
bytes
};
let first = observed(&expected);
match effect {
1 | 2 => expected[offset as usize] = 0xa5,
3 | 4 => expected[offset as usize] = input as u8,
_ => {}
}
let second = observed(&expected);
expected[16..24].copy_from_slice(&first);
expected[24..32].copy_from_slice(&second);
assert_eq!(unsafe { jit.call(&mut state) }, 0);
assert_eq!(
&state[..96],
&expected[..96],
"wide={wide:?} narrow={narrow:?} displacement={displacement} effect={effect} input={input:#x}"
);
}
}
}
}
}
}
#[test]
fn local_forwarding_preserves_narrow_values_and_physical_write_effects() {
for size in [OpSize::S8, OpSize::S16, OpSize::S32, OpSize::S64] {
for effect in 0..5 {
let mut vregs = VRegAllocator::new();
for _ in 0..5 {
vregs.alloc();
}
let mut function = MFunction::new(vregs, vec![SpillDesc::transient(); 5]);
let mut block = MBlock::new(BlockId(0));
block.push(MInst::Load {
dst: VReg(0),
base: BaseReg::SimState,
offset: 0,
size: OpSize::S64,
});
block.push(MInst::LoadImm {
dst: VReg(1),
value: 0x9876_dead_bacd_a321,
});
block.push(MInst::LoadImm {
dst: VReg(2),
value: 0,
});
block.push(MInst::Store {
base: BaseReg::SimState,
offset: 8,
src: VReg(0),
size,
});
let observer = match effect {
0 => MInst::LoadIndexed {
dst: VReg(4),
base: BaseReg::SimState,
offset: 24,
index: VReg(2),
scale: 1,
size: OpSize::S64,
alias_range: MemoryAliasRange::new(24, 8),
},
1..=3 => MInst::StoreIndexed {
base: BaseReg::SimState,
offset: if effect == 1 { 24 } else { 8 },
index: VReg(2),
src: VReg(1),
size,
alias_range: match effect {
1 => MemoryAliasRange::new(24, 8),
2 => MemoryAliasRange::new(8, 8),
_ => None,
},
},
_ => MInst::MemFill {
dst_offset: 8,
byte_len: 8,
value: 0xa5,
},
};
block.push(observer);
block.push(MInst::Load {
dst: VReg(3),
base: BaseReg::SimState,
offset: 8,
size,
});
block.push(MInst::Store {
base: BaseReg::SimState,
offset: 32,
src: VReg(3),
size: OpSize::S64,
});
if effect == 0 {
block.push(MInst::Store {
base: BaseReg::SimState,
offset: 40,
src: VReg(4),
size: OpSize::S64,
});
}
block.push(MInst::Return);
function.push_block(block);
forward_local_store_loads(&mut function);
function.verify();
assert_eq!(
function.blocks[0]
.insts
.iter()
.any(|inst| matches!(inst, MInst::Load { dst: VReg(3), .. })),
effect >= 2
);
mir_legalize::legalize(&mut function);
let allocation = regalloc::run_regalloc(&mut function).unwrap();
let code = emit::emit(
&function,
&allocation.assignment,
allocation.spill_frame_size,
)
.unwrap();
let jit = JitCode::new(&code.code).unwrap();
for input in [0u64, 1, 0x1234_5678_9abc_def0, u64::MAX] {
let mut state = vec![0u8; code.required_state_size.max(48) as usize];
state[..8].copy_from_slice(&input.to_le_bytes());
assert_eq!(unsafe { jit.call(&mut state) }, 0);
let expected = match effect {
0 | 1 => input,
2 | 3 => 0x9876_dead_bacd_a321,
_ => 0xa5a5_a5a5_a5a5_a5a5,
} & machine_width_mask(size);
assert_eq!(
u64::from_le_bytes(state[32..40].try_into().unwrap()),
expected,
"size={size:?}, effect={effect}, input={input:#x}"
);
}
}
}
}