GitLab will be upgraded on 31 Jan 2023 from 2.00 pm (AEDT) to 3.00 pm (AEDT). During the update, GitLab and Mattermost services will not be available. If you have any concerns with this, please talk to us at N110 (b) CSIT building.

asm_backend.rs 110 KB
Newer Older
1
2
#![allow(unused_variables)]

3
use compiler::backend::AOT_EMIT_CONTEXT_FILE;
qinsoon's avatar
qinsoon committed
4
use compiler::backend::RegGroup;
qinsoon's avatar
qinsoon committed
5
use utils::ByteSize;
6
7
use utils::Address;
use utils::POINTER_SIZE;
8
use compiler::backend::x86_64;
9
use compiler::backend::x86_64::CodeGenerator;
qinsoon's avatar
qinsoon committed
10
use compiler::backend::{Reg, Mem};
qinsoon's avatar
qinsoon committed
11
use compiler::backend::x86_64::check_op_len;
qinsoon's avatar
qinsoon committed
12
use compiler::machine_code::MachineCode;
qinsoon's avatar
qinsoon committed
13
use vm::VM;
qinsoon's avatar
qinsoon committed
14
use runtime::ValueLocation;
15

qinsoon's avatar
qinsoon committed
16
use utils::vec_utils;
17
use utils::string_utils;
18
19
use utils::LinkedHashMap;

20
21
use ast::ptr::P;
use ast::ir::*;
qinsoon's avatar
qinsoon committed
22
use ast::types::*;
23

qinsoon's avatar
qinsoon committed
24
use std::str;
25
use std::usize;
26
use std::slice::Iter;
27
use std::ops;
qinsoon's avatar
qinsoon committed
28
29

struct ASMCode {
qinsoon's avatar
qinsoon committed
30
    name: MuName, 
qinsoon's avatar
qinsoon committed
31
    code: Vec<ASMInst>,
qinsoon's avatar
qinsoon committed
32

33
    entry:  MuName,
34
    blocks: LinkedHashMap<MuName, ASMBlock>,
qinsoon's avatar
qinsoon committed
35
36

    frame_size_patchpoints: Vec<ASMLocation>
qinsoon's avatar
qinsoon committed
37
38
}

qinsoon's avatar
qinsoon committed
39
40
41
unsafe impl Send for ASMCode {} 
unsafe impl Sync for ASMCode {}

42
impl ASMCode {
qinsoon's avatar
qinsoon committed
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
    fn get_use_locations(&self, reg: MuID) -> Vec<ASMLocation> {
        let mut ret = vec![];

        for inst in self.code.iter() {
            match inst.uses.get(&reg) {
                Some(ref locs) => {
                    ret.append(&mut locs.to_vec());
                },
                None => {}
            }
        }

        ret
    }

    fn get_define_locations(&self, reg: MuID) -> Vec<ASMLocation> {
        let mut ret = vec![];

        for inst in self.code.iter() {
            match inst.defines.get(&reg) {
                Some(ref locs) => {
                    ret.append(&mut locs.to_vec());
                },
                None => {}
            }
        }

        ret
    }

qinsoon's avatar
qinsoon committed
73
74
75
76
77
78
79
80
81
    fn is_block_start(&self, inst: usize) -> bool {
        for block in self.blocks.values() {
            if block.start_inst == inst {
                return true;
            }
        }
        false
    }

82
    fn is_last_inst_in_block(&self, inst: usize) -> bool {
qinsoon's avatar
qinsoon committed
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
        for block in self.blocks.values() {
            if block.end_inst == inst + 1 {
                return true;
            }
        }
        false
    }

    fn get_block_by_inst(&self, inst: usize) -> (&String, &ASMBlock) {
        for (name, block) in self.blocks.iter() {
            if inst >= block.start_inst && inst < block.end_inst {
                return (name, block);
            }
        }

        panic!("didnt find any block for inst {}", inst)
    }

qinsoon's avatar
qinsoon committed
101
102
103
104
105
106
107
108
109
110
    fn get_block_by_start_inst(&self, inst: usize) -> Option<&ASMBlock> {
        for block in self.blocks.values() {
            if block.start_inst == inst {
                return Some(block);
            }
        }

        None
    }

111
112
    fn rewrite_insert(
        &self,
113
114
        insert_before: LinkedHashMap<usize, Vec<Box<ASMCode>>>,
        insert_after: LinkedHashMap<usize, Vec<Box<ASMCode>>>) -> Box<ASMCode>
115
    {
116
        trace!("insert spilling code");
117
118
        let mut ret = ASMCode {
            name: self.name.clone(),
119
            entry: self.entry.clone(),
120
            code: vec![],
121
            blocks: linked_hashmap!{},
qinsoon's avatar
qinsoon committed
122
            frame_size_patchpoints: vec![]
123
124
125
126
        };

        // iterate through old machine code
        let mut inst_offset = 0;    // how many instructions has been inserted
qinsoon's avatar
qinsoon committed
127
        let mut cur_block_start = usize::MAX;
128

qinsoon's avatar
qinsoon committed
129
130
        // inst N in old machine code is N' in new machine code
        // this map stores the relationship
131
        let mut location_map : LinkedHashMap<usize, usize> = LinkedHashMap::new();
qinsoon's avatar
qinsoon committed
132

133
        for i in 0..self.number_of_insts() {
134
135
            trace!("Inst{}", i);

qinsoon's avatar
qinsoon committed
136
137
            if self.is_block_start(i) {
                cur_block_start = i + inst_offset;
138
                trace!("  block start is shifted to {}", cur_block_start);
qinsoon's avatar
qinsoon committed
139
140
            }

141
142
143
144
145
            // insert code before this instruction
            if insert_before.contains_key(&i) {
                for insert in insert_before.get(&i).unwrap() {
                    ret.append_code_sequence_all(insert);
                    inst_offset += insert.number_of_insts();
146
                    trace!("  inserted {} insts before", insert.number_of_insts());
147
148
149
150
                }
            }

            // copy this instruction
qinsoon's avatar
qinsoon committed
151
152
            let mut inst = self.code[i].clone();

qinsoon's avatar
qinsoon committed
153
154
            // old ith inst is now the (i + inst_offset)th instruction
            location_map.insert(i, i + inst_offset);
155
            trace!("  Inst{} is now Inst{}", i, i + inst_offset);
qinsoon's avatar
qinsoon committed
156

qinsoon's avatar
qinsoon committed
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
            // this instruction has been offset by several instructions('inst_offset')
            // update its info
            // 1. fix defines and uses
            for locs in inst.defines.values_mut() {
                for loc in locs {
                    debug_assert!(loc.line == i);
                    loc.line += inst_offset;
                }
            }
            for locs in inst.uses.values_mut() {
                for loc in locs {
                    debug_assert!(loc.line == i);
                    loc.line += inst_offset;
                }
            }
qinsoon's avatar
qinsoon committed
172
173
174
            // 2. we need to delete existing preds/succs - CFA is required later
            inst.preds.clear();
            inst.succs.clear();
qinsoon's avatar
qinsoon committed
175
176
            // 3. add the inst
            ret.code.push(inst);
177
178
179
180


            // insert code after this instruction
            if insert_after.contains_key(&i) {
qinsoon's avatar
qinsoon committed
181
182
183
                for insert in insert_after.get(&i).unwrap() {
                    ret.append_code_sequence_all(insert);
                    inst_offset += insert.number_of_insts();
184
                    trace!("  inserted {} insts after", insert.number_of_insts());
qinsoon's avatar
qinsoon committed
185
186
187
                }
            }

188
189
            if self.is_last_inst_in_block(i) {
                let cur_block_end = i + 1 + inst_offset;
190

qinsoon's avatar
qinsoon committed
191
192
193
                // copy the block
                let (name, block) = self.get_block_by_inst(i);

qinsoon's avatar
qinsoon committed
194
                let new_block = ASMBlock{
195
196
197
198
199
200
201
202
203
204
                    start_inst: cur_block_start,
                    end_inst: cur_block_end,

                    livein: vec![],
                    liveout: vec![]
                };

                trace!("  old block: {:?}", block);
                trace!("  new block: {:?}", new_block);

qinsoon's avatar
qinsoon committed
205
206
207
208
                cur_block_start = usize::MAX;

                // add to the new code
                ret.blocks.insert(name.clone(), new_block);
209
210
211
            }
        }

qinsoon's avatar
qinsoon committed
212
213
214
215
216
        // fix patchpoint
        for patchpoint in self.frame_size_patchpoints.iter() {
            let new_patchpoint = ASMLocation {
                line: *location_map.get(&patchpoint.line).unwrap(),
                index: patchpoint.index,
qinsoon's avatar
qinsoon committed
217
218
                len: patchpoint.len,
                oplen: patchpoint.oplen
qinsoon's avatar
qinsoon committed
219
220
221
222
223
            };

            ret.frame_size_patchpoints.push(new_patchpoint);
        }

qinsoon's avatar
qinsoon committed
224
225
226
        ret.control_flow_analysis();

        Box::new(ret)
227
228
229
230
231
232
233
234
    }

    fn append_code_sequence(
        &mut self,
        another: &Box<ASMCode>,
        start_inst: usize,
        n_insts: usize)
    {
qinsoon's avatar
qinsoon committed
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
        let base_line = self.number_of_insts();

        for i in 0..n_insts {
            let cur_line_in_self = base_line + i;
            let cur_line_from_copy = start_inst + i;

            let mut inst = another.code[cur_line_from_copy].clone();

            // fix info
            for locs in inst.defines.values_mut() {
                for loc in locs {
                    debug_assert!(loc.line == i);
                    loc.line = cur_line_in_self;
                }
            }
            for locs in inst.uses.values_mut() {
                for loc in locs {
                    debug_assert!(loc.line == i);
                    loc.line = cur_line_in_self;
                }
            }
            // ignore preds/succs

            // add to self
            self.code.push(inst);
        }
261
262
263
264
265
266
    }

    fn append_code_sequence_all(&mut self, another: &Box<ASMCode>) {
        let n_insts = another.number_of_insts();
        self.append_code_sequence(another, 0, n_insts)
    }
qinsoon's avatar
qinsoon committed
267
268

    fn control_flow_analysis(&mut self) {
269
        const TRACE_CFA : bool = true;
qinsoon's avatar
qinsoon committed
270
271
272
273
274
275
276
277
278
279

        // control flow analysis
        let n_insts = self.number_of_insts();

        let ref blocks = self.blocks;
        let ref mut asm = self.code;

        let block_start = {
            let mut ret = vec![];
            for block in blocks.values() {
280
281
282
                if TRACE_CFA {
                    trace!("Block starts at {}", block.start_inst);
                }
qinsoon's avatar
qinsoon committed
283
284
285
286
287
288
                ret.push(block.start_inst);
            }
            ret
        };

        for i in 0..n_insts {
qinsoon's avatar
[wip]    
qinsoon committed
289
290
291
            if TRACE_CFA {
                trace!("---inst {}---", i);
            }
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320

            // skip symbol
            if asm[i].is_symbol {
                continue;
            }

            // determine predecessor

            // we check if it is a fallthrough block
            if i != 0 {
                let last_inst = ASMCode::find_prev_inst(i, asm);

                match last_inst {
                    Some(last_inst) => {
                        let last_inst_branch = asm[last_inst].branch.clone();
                        match last_inst_branch {
                            // if it is a fallthrough, we set its preds as last inst
                            ASMBranchTarget::None => {
                                if !asm[i].preds.contains(&last_inst) {
                                    asm[i].preds.push(last_inst);

                                    if TRACE_CFA {
                                        trace!("inst {}: set PREDS as previous inst - fallthrough {}", i, last_inst);
                                    }
                                }
                            }
                            // otherwise do nothing
                            _ => {}
                        }
qinsoon's avatar
qinsoon committed
321
                    }
322
                    None => {}
qinsoon's avatar
qinsoon committed
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
                }
            }

            // determine successor
            let branch = asm[i].branch.clone();
            match branch {
                ASMBranchTarget::Unconditional(ref target) => {
                    // branch to target
                    let target_n = self.blocks.get(target).unwrap().start_inst;

                    // cur inst's succ is target
                    asm[i].succs.push(target_n);

                    // target's pred is cur
                    asm[target_n].preds.push(i);

                    if TRACE_CFA {
                        trace!("inst {}: is a branch to {}", i, target);
                        trace!("inst {}: branch target index is {}", i, target_n);
                        trace!("inst {}: set SUCCS as branch target {}", i, target_n);
                        trace!("inst {}: set PREDS as branch source {}", target_n, i);
                    }
                },
                ASMBranchTarget::Conditional(ref target) => {
                    // branch to target
                    let target_n = self.blocks.get(target).unwrap().start_inst;

350
                    // cur insts' succ is target
qinsoon's avatar
qinsoon committed
351
352
353
354
355
356
357
358
359
360
361
362
363
                    asm[i].succs.push(target_n);

                    if TRACE_CFA {
                        trace!("inst {}: is a cond branch to {}", i, target);
                        trace!("inst {}: branch target index is {}", i, target_n);
                        trace!("inst {}: set SUCCS as branch target {}", i, target_n);
                    }

                    // target's pred is cur
                    asm[target_n].preds.push(i);
                    if TRACE_CFA {
                        trace!("inst {}: set PREDS as {}", target_n, i);
                    }
364
365
366
367
368
369
370
371
372
373
374
375
376
377

                    if let Some(next_inst) = ASMCode::find_next_inst(i, asm) {
                        // cur succ is next inst
                        asm[i].succs.push(next_inst);

                        // next inst's pred is cur
                        asm[next_inst].preds.push(i);

                        if TRACE_CFA {
                            trace!("inst {}: SET SUCCS as c-branch fallthrough target {}", i, next_inst);
                        }
                    } else {
                        panic!("conditional branch does not have a fallthrough target");
                    }
qinsoon's avatar
qinsoon committed
378
                },
qinsoon's avatar
[wip]    
qinsoon committed
379
380
381
382
383
384
                ASMBranchTarget::Return => {
                    if TRACE_CFA {
                        trace!("inst {}: is a return", i);
                        trace!("inst {}: has no successor", i);
                    }
                }
qinsoon's avatar
qinsoon committed
385
386
387
388
389
                ASMBranchTarget::None => {
                    // not branch nor cond branch, succ is next inst
                    if TRACE_CFA {
                        trace!("inst {}: not a branch inst", i);
                    }
390
                    if let Some(next_inst) = ASMCode::find_next_inst(i, asm) {
qinsoon's avatar
qinsoon committed
391
                        if TRACE_CFA {
392
                            trace!("inst {}: set SUCCS as next inst {}", i, next_inst);
qinsoon's avatar
qinsoon committed
393
                        }
394
                        asm[i].succs.push(next_inst);
qinsoon's avatar
qinsoon committed
395
396
397
398
                    }
                }
            }
        }
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
    }

    fn find_prev_inst(i: usize, asm: &Vec<ASMInst>) -> Option<usize> {
        if i == 0 {
            None
        } else {
            let mut cur = i - 1;
            while cur != 0 {
                if !asm[cur].is_symbol {
                    return Some(cur);
                }

                if cur == 0 {
                    return None;
                } else {
                    cur -= 1;
                }
            }

            None
        }
    }
qinsoon's avatar
qinsoon committed
421

422
423
424
425
426
427
428
429
430
431
432
    fn find_next_inst(i: usize, asm: &Vec<ASMInst>) -> Option<usize> {
        if i >= asm.len() - 1 {
            None
        } else {
            let mut cur = i + 1;
            while cur < asm.len() {
                if !asm[cur].is_symbol {
                    return Some(cur);
                }

                cur += 1;
qinsoon's avatar
qinsoon committed
433
            }
434
435

            None
qinsoon's avatar
qinsoon committed
436
437
        }
    }
qinsoon's avatar
qinsoon committed
438
439
440
441

    fn add_frame_size_patchpoint(&mut self, patchpoint: ASMLocation) {
        self.frame_size_patchpoints.push(patchpoint);
    }
442
443
444
445
}

use std::any::Any;

446
impl MachineCode for ASMCode {
447
448
449
    fn as_any(&self) -> &Any {
        self
    }
450
451
452
    fn number_of_insts(&self) -> usize {
        self.code.len()
    }
qinsoon's avatar
qinsoon committed
453
    
454
455
456
    fn is_move(&self, index: usize) -> bool {
        let inst = self.code.get(index);
        match inst {
qinsoon's avatar
qinsoon committed
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
            Some(inst) => {
                let ref inst = inst.code;

                if inst.starts_with("movsd") || inst.starts_with("movss") {
                    // floating point move
                    true
                } else if inst.starts_with("movs") || inst.starts_with("movz") {
                    // sign extend, zero extend
                    false
                } else if inst.starts_with("mov") {
                    // normal mov
                    true
                } else {
                    false
                }
            },
473
474
475
476
            None => false
        }
    }
    
qinsoon's avatar
qinsoon committed
477
    fn is_using_mem_op(&self, index: usize) -> bool {
qinsoon's avatar
qinsoon committed
478
        self.code[index].is_mem_op_used
qinsoon's avatar
qinsoon committed
479
    }
480
481
482
483
484
485
486

    fn is_jmp(&self, index: usize) -> Option<MuName> {
        let inst = self.code.get(index);
        match inst {
            Some(inst) if inst.code.starts_with("jmp") => {
                let split : Vec<&str> = inst.code.split(' ').collect();

487
                Some(ASMCodeGen::unmangle_block_label(self.name.clone(), String::from(split[1])))
488
489
490
491
492
493
494
495
496
497
498
            }
            _ => None
        }
    }

    fn is_label(&self, index: usize) -> Option<MuName> {
        let inst = self.code.get(index);
        match inst {
            Some(inst) if inst.code.ends_with(':') => {
                let split : Vec<&str> = inst.code.split(':').collect();

499
                Some(ASMCodeGen::unmangle_block_label(self.name.clone(), String::from(split[0])))
500
501
502
503
            }
            _ => None
        }
    }
qinsoon's avatar
qinsoon committed
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525

    fn is_spill_load(&self, index: usize) -> Option<P<Value>> {
        if let Some(inst) = self.code.get(index) {
            match inst.spill_info {
                Some(SpillMemInfo::Load(ref p)) => Some(p.clone()),
                _ => None
            }
        } else {
            None
        }
    }

    fn is_spill_store(&self, index: usize) -> Option<P<Value>> {
        if let Some(inst) = self.code.get(index) {
            match inst.spill_info {
                Some(SpillMemInfo::Store(ref p)) => Some(p.clone()),
                _ => None
            }
        } else {
            None
        }
    }
qinsoon's avatar
qinsoon committed
526
    
qinsoon's avatar
qinsoon committed
527
    fn get_succs(&self, index: usize) -> &Vec<usize> {
qinsoon's avatar
qinsoon committed
528
        &self.code[index].succs
qinsoon's avatar
qinsoon committed
529
530
531
    }
    
    fn get_preds(&self, index: usize) -> &Vec<usize> {
qinsoon's avatar
qinsoon committed
532
        &self.code[index].preds
qinsoon's avatar
qinsoon committed
533
534
    }
    
qinsoon's avatar
qinsoon committed
535
536
    fn get_inst_reg_uses(&self, index: usize) -> Vec<MuID> {
        self.code[index].uses.keys().map(|x| *x).collect()
537
538
    }
    
qinsoon's avatar
qinsoon committed
539
540
    fn get_inst_reg_defines(&self, index: usize) -> Vec<MuID> {
        self.code[index].defines.keys().map(|x| *x).collect()
541
    }
542
    
543
    fn replace_reg(&mut self, from: MuID, to: MuID) {
qinsoon's avatar
qinsoon committed
544
545
        for loc in self.get_define_locations(from) {
            let ref mut inst_to_patch = self.code[loc.line];
qinsoon's avatar
qinsoon committed
546
547
548
549
550
551
552

            // pick the right reg based on length
            let to_reg = x86_64::get_alias_for_length(to, loc.oplen);
            let to_reg_tag = to_reg.name().unwrap();
            let to_reg_string = "%".to_string() + &to_reg_tag;

            string_utils::replace(&mut inst_to_patch.code, loc.index, &to_reg_string, to_reg_string.len());
553
        }
554

qinsoon's avatar
qinsoon committed
555
556
        for loc in self.get_use_locations(from) {
            let ref mut inst_to_patch = self.code[loc.line];
qinsoon's avatar
qinsoon committed
557
558
559
560
561
562
563

            // pick the right reg based on length
            let to_reg = x86_64::get_alias_for_length(to, loc.oplen);
            let to_reg_tag = to_reg.name().unwrap();
            let to_reg_string = "%".to_string() + &to_reg_tag;

            string_utils::replace(&mut inst_to_patch.code, loc.index, &to_reg_string, to_reg_string.len());
564
565
        }
    }
566

567
    fn replace_define_tmp_for_inst(&mut self, from: MuID, to: MuID, inst: usize) {
qinsoon's avatar
qinsoon committed
568
        let to_reg_string : MuName = REG_PLACEHOLDER.clone();
569

qinsoon's avatar
qinsoon committed
570
571
572
573
574
575
        let asm = &mut self.code[inst];
        // if this reg is defined, replace the define
        if asm.defines.contains_key(&from) {
            let define_locs = asm.defines.get(&from).unwrap().to_vec();
            // replace temps
            for loc in define_locs.iter() {
qinsoon's avatar
qinsoon committed
576
                string_utils::replace(&mut asm.code, loc.index, &to_reg_string, to_reg_string.len());
577
578
            }

qinsoon's avatar
qinsoon committed
579
580
            // remove old key, insert new one
            asm.defines.remove(&from);
581
            asm.defines.insert(to, define_locs);
582
        }
583
584
585
    }

    fn replace_use_tmp_for_inst(&mut self, from: MuID, to: MuID, inst: usize) {
qinsoon's avatar
qinsoon committed
586
        let to_reg_string : MuName = REG_PLACEHOLDER.clone();
587
588

        let asm = &mut self.code[inst];
qinsoon's avatar
qinsoon committed
589
590
591
592
593
594

        // if this reg is used, replace the use
        if asm.uses.contains_key(&from) {
            let use_locs = asm.uses.get(&from).unwrap().to_vec();
            // replace temps
            for loc in use_locs.iter() {
qinsoon's avatar
qinsoon committed
595
                string_utils::replace(&mut asm.code, loc.index, &to_reg_string, to_reg_string.len());
596
597
            }

qinsoon's avatar
qinsoon committed
598
599
            // remove old key, insert new one
            asm.uses.remove(&from);
600
            asm.uses.insert(to, use_locs);
601
602
        }
    }
603
    
604
605
    fn set_inst_nop(&mut self, index: usize) {
        self.code.remove(index);
qinsoon's avatar
qinsoon committed
606
        self.code.insert(index, ASMInst::nop());
607
    }
qinsoon's avatar
qinsoon committed
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657

    fn remove_unnecessary_callee_saved(&mut self, used_callee_saved: Vec<MuID>) -> Vec<MuID> {
        // we always save rbp
        let rbp = x86_64::RBP.extract_ssa_id().unwrap();
        // every push/pop will use/define rsp
        let rsp = x86_64::RSP.extract_ssa_id().unwrap();

        let find_op_other_than_rsp = |inst: &ASMInst| -> Option<MuID> {
            for id in inst.defines.keys() {
                if *id != rsp && *id != rbp {
                    return Some(*id);
                }
            }
            for id in inst.uses.keys() {
                if *id != rsp && *id != rbp {
                    return Some(*id);
                }
            }

            None
        };

        let mut inst_to_remove = vec![];
        let mut regs_to_remove = vec![];

        for i in 0..self.number_of_insts() {
            let ref inst = self.code[i];

            if inst.code.contains("push") || inst.code.contains("pop") {
                match find_op_other_than_rsp(inst) {
                    Some(op) => {
                        // if this push/pop instruction is about a callee saved register
                        // and the register is not used, we set the instruction as nop
                        if x86_64::is_callee_saved(op) && !used_callee_saved.contains(&op) {
                            trace!("removing instruction {:?} for save/restore unnecessary callee saved regs", inst);
                            regs_to_remove.push(op);
                            inst_to_remove.push(i);
                        }
                    }
                    None => {}
                }
            }
        }

        for i in inst_to_remove {
            self.set_inst_nop(i);
        }

        regs_to_remove
    }
qinsoon's avatar
qinsoon committed
658

659
660
661
662
663
664
665
666
667
    fn patch_frame_size(&mut self, size: usize, size_used: usize) {
        // calling convention requires stack pointer to be 16 bytes aligned before a call
        // we make frame size a multipl of 16 bytes
        let size = if (size + size_used) % 16 == 0 {
            size
        } else {
            ( (size + size_used) / 16 + 1) * 16 - size_used
        };

qinsoon's avatar
qinsoon committed
668
669
670
671
672
673
674
675
676
677
        let size = size.to_string();

        debug_assert!(size.len() <= FRAME_SIZE_PLACEHOLDER_LEN);

        for loc in self.frame_size_patchpoints.iter() {
            let ref mut inst = self.code[loc.line];

            string_utils::replace(&mut inst.code, loc.index, &size, size.len());
        }
    }
678
    
679
680
681
682
683
684
685
686
687
688
689
    fn emit(&self) -> Vec<u8> {
        let mut ret = vec![];
        
        for inst in self.code.iter() {
            ret.append(&mut inst.code.clone().into_bytes());
            ret.append(&mut "\n".to_string().into_bytes());
        }
        
        ret
    }
    
690
691
    fn trace_mc(&self) {
        trace!("");
692

693
694
        trace!("code for {}: \n", self.name);
        
695
696
        let n_insts = self.code.len();
        for i in 0..n_insts {
697
            self.trace_inst(i);
698
699
        }
        
700
701
702
703
704
705
        trace!("")      
    }
    
    fn trace_inst(&self, i: usize) {
        trace!("#{}\t{:30}\t\tdefine: {:?}\tuses: {:?}\tpred: {:?}\tsucc: {:?}", 
            i, self.code[i].code, self.get_inst_reg_defines(i), self.get_inst_reg_uses(i),
qinsoon's avatar
qinsoon committed
706
            self.code[i].preds, self.code[i].succs);
707
    }
708
    
709
    fn get_ir_block_livein(&self, block: &str) -> Option<&Vec<MuID>> {
qinsoon's avatar
qinsoon committed
710
711
712
713
        match self.blocks.get(block) {
            Some(ref block) => Some(&block.livein),
            None => None
        }
714
715
    }
    
716
    fn get_ir_block_liveout(&self, block: &str) -> Option<&Vec<MuID>> {
qinsoon's avatar
qinsoon committed
717
718
719
720
        match self.blocks.get(block) {
            Some(ref block) => Some(&block.liveout),
            None => None
        }
721
722
    }
    
723
    fn set_ir_block_livein(&mut self, block: &str, set: Vec<MuID>) {
qinsoon's avatar
qinsoon committed
724
725
        let block = self.blocks.get_mut(block).unwrap();
        block.livein = set;
726
727
728
    }
    
    fn set_ir_block_liveout(&mut self, block: &str, set: Vec<MuID>) {
qinsoon's avatar
qinsoon committed
729
730
        let block = self.blocks.get_mut(block).unwrap();
        block.liveout = set;
731
732
    }
    
qinsoon's avatar
qinsoon committed
733
734
    fn get_all_blocks(&self) -> Vec<MuName> {
        self.blocks.keys().map(|x| x.clone()).collect()
735
    }
736
737
738
739

    fn get_entry_block(&self) -> MuName {
        self.entry.clone()
    }
740
    
741
    fn get_block_range(&self, block: &str) -> Option<ops::Range<usize>> {
qinsoon's avatar
qinsoon committed
742
743
        match self.blocks.get(block) {
            Some(ref block) => Some(block.start_inst..block.end_inst),
744
745
746
            None => None
        }
    }
747
748
}

qinsoon's avatar
qinsoon committed
749
750
751
752
#[derive(Clone, Debug)]
enum ASMBranchTarget {
    None,
    Conditional(MuName),
qinsoon's avatar
[wip]    
qinsoon committed
753
754
    Unconditional(MuName),
    Return
qinsoon's avatar
qinsoon committed
755
756
}

757
758
759
760
761
762
#[derive(Clone, Debug)]
enum SpillMemInfo {
    Load(P<Value>),
    Store(P<Value>)
}

qinsoon's avatar
qinsoon committed
763
#[derive(Clone, Debug)]
qinsoon's avatar
qinsoon committed
764
struct ASMInst {
765
    code: String,
qinsoon's avatar
qinsoon committed
766

767
768
    defines: LinkedHashMap<MuID, Vec<ASMLocation>>,
    uses: LinkedHashMap<MuID, Vec<ASMLocation>>,
qinsoon's avatar
qinsoon committed
769
770

    is_mem_op_used: bool,
771
772
    is_symbol: bool,

qinsoon's avatar
qinsoon committed
773
774
    preds: Vec<usize>,
    succs: Vec<usize>,
775
776
777
    branch: ASMBranchTarget,

    spill_info: Option<SpillMemInfo>
qinsoon's avatar
qinsoon committed
778
779
}

qinsoon's avatar
qinsoon committed
780
781
782
impl ASMInst {
    fn symbolic(line: String) -> ASMInst {
        ASMInst {
783
            code: line,
784
785
            defines: LinkedHashMap::new(),
            uses: LinkedHashMap::new(),
qinsoon's avatar
qinsoon committed
786
            is_mem_op_used: false,
787
            is_symbol: true,
qinsoon's avatar
qinsoon committed
788
789
            preds: vec![],
            succs: vec![],
790
791
792
            branch: ASMBranchTarget::None,

            spill_info: None
793
794
795
        }
    }
    
qinsoon's avatar
qinsoon committed
796
797
    fn inst(
        inst: String,
798
799
        defines: LinkedHashMap<MuID, Vec<ASMLocation>>,
        uses: LinkedHashMap<MuID, Vec<ASMLocation>>,
qinsoon's avatar
qinsoon committed
800
        is_mem_op_used: bool,
801
802
        target: ASMBranchTarget,
        spill_info: Option<SpillMemInfo>
qinsoon's avatar
qinsoon committed
803
804
805
    ) -> ASMInst
    {
        ASMInst {
806
807
            code: inst,
            defines: defines,
qinsoon's avatar
qinsoon committed
808
            uses: uses,
809
            is_symbol: false,
qinsoon's avatar
qinsoon committed
810
811
812
            is_mem_op_used: is_mem_op_used,
            preds: vec![],
            succs: vec![],
813
814
815
            branch: target,

            spill_info: spill_info
816
817
        }
    }
818
    
qinsoon's avatar
qinsoon committed
819
820
    fn nop() -> ASMInst {
        ASMInst {
821
            code: "".to_string(),
822
823
            defines: LinkedHashMap::new(),
            uses: LinkedHashMap::new(),
824
            is_symbol: false,
qinsoon's avatar
qinsoon committed
825
826
827
            is_mem_op_used: false,
            preds: vec![],
            succs: vec![],
828
829
830
            branch: ASMBranchTarget::None,

            spill_info: None
831
832
        }
    }
qinsoon's avatar
qinsoon committed
833
834
}

835
#[derive(Clone, Debug, PartialEq, Eq)]
qinsoon's avatar
qinsoon committed
836
837
838
struct ASMLocation {
    line: usize,
    index: usize,
qinsoon's avatar
qinsoon committed
839
840
    len: usize,
    oplen: usize,
qinsoon's avatar
qinsoon committed
841
842
843
}

impl ASMLocation {
qinsoon's avatar
qinsoon committed
844
    fn new(line: usize, index: usize, len: usize, oplen: usize) -> ASMLocation {
qinsoon's avatar
qinsoon committed
845
        ASMLocation{
qinsoon's avatar
qinsoon committed
846
            line: line,
qinsoon's avatar
qinsoon committed
847
            index: index,
qinsoon's avatar
qinsoon committed
848
849
            len: len,
            oplen: oplen
qinsoon's avatar
qinsoon committed
850
851
852
853
        }
    }
}

qinsoon's avatar
qinsoon committed
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
#[derive(Clone, Debug)]
/// [start_inst, end_inst)
struct ASMBlock {
    start_inst: usize,
    end_inst: usize,

    livein: Vec<MuID>,
    liveout: Vec<MuID>
}

impl ASMBlock {
    fn new() -> ASMBlock {
        ASMBlock {
            start_inst: usize::MAX,
            end_inst: usize::MAX,
            livein: vec![],
            liveout: vec![]
        }
    }
}

875
pub struct ASMCodeGen {
876
    cur: Option<Box<ASMCode>>
877
878
}

879
const REG_PLACEHOLDER_LEN : usize = 5;
qinsoon's avatar
qinsoon committed
880
881
882
883
884
885
lazy_static! {
    pub static ref REG_PLACEHOLDER : String = {
        let blank_spaces = [' ' as u8; REG_PLACEHOLDER_LEN];
        
        format!("%{}", str::from_utf8(&blank_spaces).unwrap())
    };
886
887
}

qinsoon's avatar
qinsoon committed
888
889
890
891
892
893
894
895
const FRAME_SIZE_PLACEHOLDER_LEN : usize = 10; // a frame is smaller than 1 << 10
lazy_static! {
    pub static ref FRAME_SIZE_PLACEHOLDER : String = {
        let blank_spaces = [' ' as u8; FRAME_SIZE_PLACEHOLDER_LEN];
        format!("{}", str::from_utf8(&blank_spaces).unwrap())
    };
}

896
897
impl ASMCodeGen {
    pub fn new() -> ASMCodeGen {
qinsoon's avatar
qinsoon committed
898
        ASMCodeGen {
899
            cur: None
qinsoon's avatar
qinsoon committed
900
901
902
903
904
905
906
907
908
909
910
        }
    }
    
    fn cur(&self) -> &ASMCode {
        self.cur.as_ref().unwrap()
    }
    
    fn cur_mut(&mut self) -> &mut ASMCode {
        self.cur.as_mut().unwrap()
    }
    
911
912
913
914
    fn line(&self) -> usize {
        self.cur().code.len()
    }
    
915
916
    fn add_asm_label(&mut self, code: String) {
        let l = self.line();
qinsoon's avatar
qinsoon committed
917
        self.cur_mut().code.push(ASMInst::symbolic(code));
918
919
    }
    
920
    fn add_asm_block_label(&mut self, code: String, block_name: MuName) {
921
        let l = self.line();
qinsoon's avatar
qinsoon committed
922
        self.cur_mut().code.push(ASMInst::symbolic(code));
923
924
    }
    
925
    fn add_asm_symbolic(&mut self, code: String){
qinsoon's avatar
qinsoon committed
926
        self.cur_mut().code.push(ASMInst::symbolic(code));
927
928
    }
    
929
930
    fn prepare_machine_regs(&self, regs: Iter<P<Value>>) -> Vec<MuID> {
        regs.map(|x| self.prepare_machine_reg(x)).collect()
qinsoon's avatar
qinsoon committed
931
    }
932
    
933
    fn add_asm_call(&mut self, code: String) {
qinsoon's avatar
qinsoon committed
934
        // a call instruction will use all the argument registers
qinsoon's avatar
qinsoon committed
935
        // do not need
936
        let uses : LinkedHashMap<MuID, Vec<ASMLocation>> = LinkedHashMap::new();
qinsoon's avatar
qinsoon committed
937
938
939
940
941
942
//        for reg in x86_64::ARGUMENT_GPRs.iter() {
//            uses.insert(reg.id(), vec![]);
//        }
//        for reg in x86_64::ARGUMENT_FPRs.iter() {
//            uses.insert(reg.id(), vec![]);
//        }
qinsoon's avatar
qinsoon committed
943
944

        // defines: return registers
945
        let mut defines : LinkedHashMap<MuID, Vec<ASMLocation>> = LinkedHashMap::new();
qinsoon's avatar
qinsoon committed
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
        for reg in x86_64::RETURN_GPRs.iter() {
            defines.insert(reg.id(), vec![]);
        }
        for reg in x86_64::RETURN_FPRs.iter() {
            defines.insert(reg.id(), vec![]);
        }
        for reg in x86_64::CALLER_SAVED_GPRs.iter() {
            if !defines.contains_key(&reg.id()) {
                defines.insert(reg.id(), vec![]);
            }
        }
        for reg in x86_64::CALLER_SAVED_FPRs.iter() {
            if !defines.contains_key(&reg.id()) {
                defines.insert(reg.id(), vec![]);
            }
        }
962
          
qinsoon's avatar
qinsoon committed
963
        self.add_asm_inst(code, defines, uses, false);
964
965
966
    }
    
    fn add_asm_ret(&mut self, code: String) {
967
968
969
970
        // return instruction does not use anything (not RETURN REGS)
        // otherwise it will keep RETURN REGS alive
        // and if there is no actual move into RETURN REGS, it will keep RETURN REGS for alive for very long
        // and prevents anything using those regsiters
971
        self.add_asm_inst_internal(code, linked_hashmap!{}, linked_hashmap!{}, false, ASMBranchTarget::Return, None);
972
973
    }
    
974
    fn add_asm_branch(&mut self, code: String, target: MuName) {
975
        self.add_asm_inst_internal(code, linked_hashmap!{}, linked_hashmap!{}, false, ASMBranchTarget::Unconditional(target), None);
976
977
    }
    
978
    fn add_asm_branch2(&mut self, code: String, target: MuName) {
979
        self.add_asm_inst_internal(code, linked_hashmap!{}, linked_hashmap!{}, false, ASMBranchTarget::Conditional(target), None);
980
981
982
983
984
    }
    
    fn add_asm_inst(
        &mut self, 
        code: String, 
985
986
        defines: LinkedHashMap<MuID, Vec<ASMLocation>>,
        uses: LinkedHashMap<MuID, Vec<ASMLocation>>,
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
        is_using_mem_op: bool
    ) {
        self.add_asm_inst_internal(code, defines, uses, is_using_mem_op, ASMBranchTarget::None, None)
    }

    fn add_asm_inst_with_spill(
        &mut self,
        code: String,
        defines: LinkedHashMap<MuID, Vec<ASMLocation>>,
        uses: LinkedHashMap<MuID, Vec<ASMLocation>>,
        is_using_mem_op: bool,
        spill_info: SpillMemInfo
    ) {
        self.add_asm_inst_internal(code, defines, uses, is_using_mem_op, ASMBranchTarget::None, Some(spill_info))
qinsoon's avatar
qinsoon committed
1001
1002
1003
1004
1005
    }

    fn add_asm_inst_internal(
        &mut self,
        code: String,
1006
1007
        defines: LinkedHashMap<MuID, Vec<ASMLocation>>,
        uses: LinkedHashMap<MuID, Vec<ASMLocation>>,
qinsoon's avatar
qinsoon committed
1008
        is_using_mem_op: bool,
1009
1010
        target: ASMBranchTarget,
        spill_info: Option<SpillMemInfo>)
1011
    {
1012
1013
        let line = self.line();
        trace!("asm: {}", code);
qinsoon's avatar
qinsoon committed
1014
1015
        trace!("     defines: {:?}", defines);
        trace!("     uses: {:?}", uses);
1016
        let mc = self.cur_mut();
qinsoon's avatar
qinsoon committed
1017

1018
        // put the instruction
1019
        mc.code.push(ASMInst::inst(code, defines, uses, is_using_mem_op, target, spill_info));
qinsoon's avatar
qinsoon committed
1020
1021
    }
    
1022
    fn prepare_reg(&self, op: &P<Value>, loc: usize) -> (String, MuID, ASMLocation) {
1023
1024
1025
1026
1027
1028
1029
        if cfg!(debug_assertions) {
            match op.v {
                Value_::SSAVar(_) => {},
                _ => panic!("expecting register op")
            }
        }
        
1030
1031
        let str = self.asm_reg_op(op);
        let len = str.len();
qinsoon's avatar
qinsoon committed
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
        (str, op.extract_ssa_id().unwrap(), ASMLocation::new(self.line(), loc, len, check_op_len(op)))
    }

    fn prepare_fpreg(&self, op: &P<Value>, loc: usize) -> (String, MuID, ASMLocation) {
        if cfg!(debug_assertions) {
            match op.v {
                Value_::SSAVar(_) => {},
                _ => panic!("expecting register op")
            }
        }

        let str = self.asm_reg_op(op);
        let len = str.len();
        (str, op.extract_ssa_id().unwrap(), ASMLocation::new(self.line(), loc, len, 64))
1046
1047
1048
    }
    
    fn prepare_machine_reg(&self, op: &P<Value>) -> MuID {
1049
1050
1051
1052
1053
1054
1055
        if cfg!(debug_assertions) {
            match op.v {
                Value_::SSAVar(_) => {},
                _ => panic!("expecting machine register op")
            }
        }        
        
1056
        op.extract_ssa_id().unwrap()
1057
    }
1058
    
1059
    #[allow(unused_assignments)]
1060
    fn prepare_mem(&self, op: &P<Value>, loc: usize) -> (String, LinkedHashMap<MuID, Vec<ASMLocation>>) {
1061
1062
1063
        if cfg!(debug_assertions) {
            match op.v {
                Value_::Memory(_) => {},
qinsoon's avatar
qinsoon committed
1064
                _ => panic!("expecting memory op")
1065
1066
            }
        }        
qinsoon's avatar
qinsoon committed
1067

1068
1069
1070
1071
        let mut ids : Vec<MuID> = vec![];
        let mut locs : Vec<ASMLocation> = vec![];
        let mut result_str : String = "".to_string();
        
1072
        let mut loc_cursor : usize = loc;
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
        
        match op.v {
            // offset(base,index,scale)
            Value_::Memory(MemoryLocation::Address{ref base, ref offset, ref index, scale}) => {
                // deal with offset
                if offset.is_some() {
                    let offset = offset.as_ref().unwrap();
                    
                    match offset.v {
                        Value_::SSAVar(id) => {
                            // temp as offset
qinsoon's avatar
qinsoon committed
1084
                            let (str, id, loc) = self.prepare_reg(offset, loc_cursor);
1085
1086
1087
1088
1089
1090
1091
1092
                            
                            result_str.push_str(&str);
                            ids.push(id);
                            locs.push(loc);
                            
                            loc_cursor += str.len();
                        },
                        Value_::Constant(Constant::Int(val)) => {
qinsoon's avatar
qinsoon committed
1093
                            let str = (val as i32).to_string();
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
                            
                            result_str.push_str(&str);
                            loc_cursor += str.len();
                        },
                        _ => panic!("unexpected offset type: {:?}", offset)
                    }
                }
                
                result_str.push('(');
                loc_cursor += 1; 
                
                // deal with base, base is ssa
                let (str, id, loc) = self.prepare_reg(base, loc_cursor);
                result_str.push_str(&str);
                ids.push(id);
                locs.push(loc);
                loc_cursor += str.len();
                
                // deal with index (ssa or constant)
                if index.is_some() {
                    result_str.push(',');
                    loc_cursor += 1; // plus 1 for ,                    
                    
                    let index = index.as_ref().unwrap();
                    
                    match index.v {
                        Value_::SSAVar(id) => {
                            // temp as offset
                            let (str, id, loc) = self.prepare_reg(index, loc_cursor);
                            
                            result_str.push_str(&str);
                            ids.push(id);
                            locs.push(loc);
                            
                            loc_cursor += str.len();
                        },
                        Value_::Constant(Constant::Int(val)) => {
qinsoon's avatar
qinsoon committed
1131
                            let str = (val as i32).to_string();
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
                            
                            result_str.push_str(&str);
                            loc_cursor += str.len();
                        },
                        _ => panic!("unexpected index type: {:?}", index)
                    }
                    
                    // scale
                    if scale.is_some() {
                        result_str.push(',');
                        loc_cursor += 1;
                        
                        let scale = scale.unwrap();
                        let str = scale.to_string();
                        
                        result_str.push_str(&str);
                        loc_cursor += str.len();
                    }
                }
                
                result_str.push(')');
                loc_cursor += 1;
            },
1155
1156
            Value_::Memory(MemoryLocation::Symbolic{ref base, ref label, is_global}) => {
                if base.is_some() && base.as_ref().unwrap().id() == x86_64::RIP.id() && is_global {
qinsoon's avatar
qinsoon committed
1157
                    // pc relative address
1158
1159
                    let pic_symbol = pic_symbol(label.clone());
//                    let pic_symbol = symbol(label.clone()); // not sure if we need this
qinsoon's avatar
qinsoon committed
1160
1161
1162
1163
1164
1165
1166
                    result_str.push_str(&pic_symbol);
                    loc_cursor += label.len();
                } else {
                    let symbol = symbol(label.clone());
                    result_str.push_str(&symbol);
                    loc_cursor += label.len();
                }
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
                
                if base.is_some() {
                    result_str.push('(');
                    loc_cursor += 1;
                    
                    let (str, id, loc) = self.prepare_reg(base.as_ref().unwrap(), loc_cursor);
                    result_str.push_str(&str);
                    ids.push(id);
                    locs.push(loc);
                    loc_cursor += str.len();
qinsoon's avatar
qinsoon committed
1177

1178
                    result_str.push(')');
qinsoon's avatar
qinsoon committed
1179
                    loc_cursor += 1;
1180
1181
1182
1183
                }
            },
            _ => panic!("expect mem location as value")
        }
qinsoon's avatar
qinsoon committed
1184

1185
1186
        let uses : LinkedHashMap<MuID, Vec<ASMLocation>> = {
            let mut map : LinkedHashMap<MuID, Vec<ASMLocation>> = linked_hashmap!{};
qinsoon's avatar
qinsoon committed
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
            for i in 0..ids.len() {
                let id = ids[i];
                let loc = locs[i].clone();

                if map.contains_key(&id) {
                    map.get_mut(&id).unwrap().push(loc);
                } else {
                    map.insert(id, vec![loc]);
                }
            }
            map
        };


        (result_str, uses)
1202
    }
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212

    fn prepare_imm(&self, op: i32, len: usize) -> i32 {
        match len {
            64 => op,
            32 => op,
            16 => op as i16 as i32,
            8  => op as i8  as i32,
            _ => unimplemented!()
        }
    }
1213
    
qinsoon's avatar
qinsoon committed
1214
1215
    fn asm_reg_op(&self, op: &P<Value>) -> String {
        let id = op.extract_ssa_id().unwrap();
qinsoon's avatar
qinsoon committed
1216
        if id < MACHINE_ID_END {
qinsoon's avatar
qinsoon committed
1217
            // machine reg
1218
            format!("%{}", op.name().unwrap())
qinsoon's avatar
qinsoon committed
1219
1220
1221
1222
1223
1224
        } else {
            // virtual register, use place holder
            REG_PLACEHOLDER.clone()
        }
    }
    
qinsoon's avatar
qinsoon committed
1225
1226
    fn mangle_block_label(&self, label: MuName) -> String {
        format!("{}_{}", self.cur().name, label)
1227
    }
1228