T0b1/wasmtime
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Remove unreachable x64 lowerings for iadd_imm (#4726)

Browse Source 
All of the `*_imm` instructions are rewritten during legalization to an
explicit `iconst` plus the general form of the operator, so backends
never see them. Therefore these ISLE rules in the x64 backend can never
match anything.
This commit is contained in:
Jamey Sharp
2022-08-16 15:54:48 -07:00
committed by GitHub
parent 5add267b87
commit c569e7bea5
1 changed files with 0 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
cranelift/codegen/src/isa/x64/lower.isle
View File

@@ -189,37 +189,6 @@
;; (No `iadd_ifcout` for `i128`.)
;;;; Rules for `iadd_imm` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; `i64` and smaller.
;; When the immediate fits in a `RegMemImm.Imm`, use that.
(rule (lower (has_type (fits_in_64 ty) (iadd_imm y (simm32_from_imm64 x))))
(x64_add ty y x))
;; Otherwise, put the immediate into a register.
(rule (lower (has_type (fits_in_64 ty) (iadd_imm y (u64_from_imm64 x))))
(x64_add ty y (imm ty x)))
;; `i128`
;; When the immediate fits in a `RegMemImm.Imm`, use that.
(rule (lower (has_type $I128 (iadd_imm y (simm32_from_imm64 x))))
(let ((y_regs ValueRegs y)
(y_lo Gpr (value_regs_get_gpr y_regs 0))
(y_hi Gpr (value_regs_get_gpr y_regs 1)))
(with_flags (x64_add_with_flags_paired $I64 y_lo x)
(x64_adc_paired $I64 y_hi (RegMemImm.Imm 0)))))
;; Otherwise, put the immediate into a register.
(rule (lower (has_type $I128 (iadd_imm y (u64_from_imm64 x))))
(let ((y_regs ValueRegs y)
(y_lo Gpr (value_regs_get_gpr y_regs 0))
(y_hi Gpr (value_regs_get_gpr y_regs 1))
(x_lo Gpr (imm $I64 x)))
(with_flags (x64_add_with_flags_paired $I64 y_lo x_lo)
(x64_adc_paired $I64 y_hi (RegMemImm.Imm 0)))))
;;;; Rules for `isub` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; `i64` and smaller.