cranelift: Remove redundant branch and select instructions (#5097)

As discussed in the 2022/10/19 meeting, this PR removes many of the branch and select instructions that used iflags, in favor if using brz/brnz and select in their place. Additionally, it reworks selectif_spectre_guard to take an i8 input instead of an iflags input.

For reference, the removed instructions are: br_icmp, brif, brff, trueif, trueff, and selectif.
This commit is contained in:
Trevor Elliott
2022-10-24 16:14:35 -07:00
committed by GitHub
parent 30589170b4
commit ec12415b1f
40 changed files with 579 additions and 2527 deletions

View File

@@ -171,7 +171,7 @@ impl LowerBackend for S390xBackend {
| Opcode::IsNull
| Opcode::IsInvalid
| Opcode::Select
| Opcode::SelectifSpectreGuard
| Opcode::SelectSpectreGuard
| Opcode::Trap
| Opcode::ResumableTrap
| Opcode::Trapz
@@ -223,21 +223,10 @@ impl LowerBackend for S390xBackend {
Opcode::GlobalValue => {
panic!("global_value should have been removed by legalization!");
}
Opcode::Ifcmp
| Opcode::Ffcmp
| Opcode::Trapff
| Opcode::Trueif
| Opcode::Trueff
| Opcode::Selectif => {
Opcode::Ifcmp | Opcode::Ffcmp | Opcode::Trapff => {
panic!("Flags opcode should not be encountered.");
}
Opcode::Jump
| Opcode::Brz
| Opcode::Brnz
| Opcode::BrIcmp
| Opcode::Brif
| Opcode::Brff
| Opcode::BrTable => {
Opcode::Jump | Opcode::Brz | Opcode::Brnz | Opcode::BrTable => {
panic!("Branch opcode reached non-branch lowering logic!");
}
Opcode::IaddImm