rust/compiler/rustc_mir_transform
Stuart Cook 544462ad8b
Rollup merge of #152474 - sgasho:opt-bisect-limit-mir, r=saethlin
Implement opt-bisect-limit for MIR

closes: rust-lang/rust#150910

Enable bisecting MIR optimization passes to enhance debuggability.

discussions on zulip: https://rust-lang.zulipchat.com/#narrow/channel/182449-t-compiler.2Fhelp/topic/MIR.20dump.20the.20pass.20names/with/573219207

### Check it works
#### Sample code
```rust
fn abs(num: isize) -> usize {
    if num < 0 { -num as usize } else { num as usize }
}

fn main() {
    println!("{}", abs(-10));
}
```

#### Output

```shell
rustc +mir -Zmir-opt-bisect-limit=30 src/main.rs
BISECT: running pass (1) CheckAlignment on main[89d5]::main
BISECT: running pass (2) CheckNull on main[89d5]::main
BISECT: running pass (3) CheckEnums on main[89d5]::main
BISECT: running pass (4) LowerSliceLenCalls on main[89d5]::main
BISECT: running pass (5) InstSimplify-before-inline on main[89d5]::main
BISECT: running pass (6) ForceInline on main[89d5]::main
BISECT: running pass (7) RemoveStorageMarkers on main[89d5]::main
BISECT: running pass (8) RemoveZsts on main[89d5]::main
BISECT: running pass (9) RemoveUnneededDrops on main[89d5]::main
BISECT: running pass (10) UnreachableEnumBranching on main[89d5]::main
BISECT: running pass (11) SimplifyCfg-after-unreachable-enum-branching on main[89d5]::main
BISECT: running pass (12) InstSimplify-after-simplifycfg on main[89d5]::main
BISECT: running pass (13) SimplifyConstCondition-after-inst-simplify on main[89d5]::main
BISECT: running pass (14) SimplifyLocals-before-const-prop on main[89d5]::main
BISECT: running pass (15) SimplifyLocals-after-value-numbering on main[89d5]::main
BISECT: running pass (16) MatchBranchSimplification on main[89d5]::main
BISECT: running pass (17) SingleUseConsts on main[89d5]::main
BISECT: running pass (18) SimplifyConstCondition-after-const-prop on main[89d5]::main
BISECT: running pass (19) SimplifyConstCondition-final on main[89d5]::main
BISECT: running pass (20) RemoveNoopLandingPads on main[89d5]::main
BISECT: running pass (21) SimplifyCfg-final on main[89d5]::main
BISECT: running pass (22) CopyProp on main[89d5]::main
BISECT: running pass (23) SimplifyLocals-final on main[89d5]::main
BISECT: running pass (24) AddCallGuards on main[89d5]::main
BISECT: running pass (25) PreCodegen on main[89d5]::main
BISECT: running pass (26) CheckAlignment on main[89d5]::abs
BISECT: running pass (27) CheckNull on main[89d5]::abs
BISECT: running pass (28) CheckEnums on main[89d5]::abs
BISECT: running pass (29) LowerSliceLenCalls on main[89d5]::abs
BISECT: running pass (30) InstSimplify-before-inline on main[89d5]::abs
BISECT: NOT running pass (31) ForceInline on main[89d5]::abs
BISECT: NOT running pass (32) RemoveStorageMarkers on main[89d5]::abs
BISECT: NOT running pass (33) RemoveZsts on main[89d5]::abs
BISECT: NOT running pass (34) RemoveUnneededDrops on main[89d5]::abs
BISECT: NOT running pass (35) UnreachableEnumBranching on main[89d5]::abs
BISECT: NOT running pass (36) SimplifyCfg-after-unreachable-enum-branching on main[89d5]::abs
BISECT: NOT running pass (37) InstSimplify-after-simplifycfg on main[89d5]::abs
BISECT: NOT running pass (38) SimplifyConstCondition-after-inst-simplify on main[89d5]::abs
BISECT: NOT running pass (39) SimplifyLocals-before-const-prop on main[89d5]::abs
BISECT: NOT running pass (40) SimplifyLocals-after-value-numbering on main[89d5]::abs
BISECT: NOT running pass (41) MatchBranchSimplification on main[89d5]::abs
BISECT: NOT running pass (42) SingleUseConsts on main[89d5]::abs
BISECT: NOT running pass (43) SimplifyConstCondition-after-const-prop on main[89d5]::abs
BISECT: NOT running pass (44) SimplifyConstCondition-final on main[89d5]::abs
BISECT: NOT running pass (45) RemoveNoopLandingPads on main[89d5]::abs
BISECT: NOT running pass (46) SimplifyCfg-final on main[89d5]::abs
BISECT: NOT running pass (47) CopyProp on main[89d5]::abs
BISECT: NOT running pass (48) SimplifyLocals-final on main[89d5]::abs
BISECT: NOT running pass (49) AddCallGuards on main[89d5]::abs
BISECT: NOT running pass (50) PreCodegen on main[89d5]::abs
```

r? @saethlin
2026-02-18 17:29:46 +11:00
..
src Rollup merge of #152474 - sgasho:opt-bisect-limit-mir, r=saethlin 2026-02-18 17:29:46 +11:00
Cargo.toml Convert to inline diagnostics in rustc_mir_transform 2026-02-04 18:29:47 +01:00