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

Cranelift: Only build iconst for ints <= 64 bits (#5723)

Browse Source 
I audited the egraph "algebraic" optimization rules for any which
construct an `iconst` on the right-hand side of the rule. In these cases
we need to constrain the type passed to `iconst` to be both `fits_in_64`
and `ty_int`, because `iconst` is not defined on other types.
This commit is contained in:
Jamey Sharp
2023-02-06 14:10:29 -08:00
committed by GitHub
parent 284fec127a
commit 65c1f654f2
1 changed files with 14 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
cranelift/codegen/src/opts/algebraic.isle
View File

@@ -101,7 +101,7 @@
(subsume x)) (subsume x))
;; x ^ x == 0. ;; x ^ x == 0.
(rule (simplify (bxor (fits_in_64 ty) x x)) (rule (simplify (bxor (fits_in_64 (ty_int ty)) x x))
(subsume (iconst ty (imm64 0)))) (subsume (iconst ty (imm64 0))))
;; x ^ not(x) == not(x) ^ x == -1. ;; x ^ not(x) == not(x) ^ x == -1.
@@ -167,6 +167,9 @@
(iadd ty x x)) (iadd ty x x))
;; x*c == x<<log2(c) when c is a power of two. ;; x*c == x<<log2(c) when c is a power of two.
;; Note that the type of `iconst` must be the same as the type of `imul`,
;; so these rules can only fire in situations where it's safe to construct an
;; `iconst` of that type.
(rule (simplify (imul ty x (iconst _ (imm64_power_of_two c)))) (rule (simplify (imul ty x (iconst _ (imm64_power_of_two c))))
(ishl ty x (iconst ty (imm64 c)))) (ishl ty x (iconst ty (imm64 c))))
(rule (simplify (imul ty (iconst _ (imm64_power_of_two c)) x)) (rule (simplify (imul ty (iconst _ (imm64_power_of_two c)) x))
@@ -252,34 +255,34 @@
;; `x == x` is always true for integers; `x != x` is false. Strict ;; `x == x` is always true for integers; `x != x` is false. Strict
;; inequalities are false, and loose inequalities are true. ;; inequalities are false, and loose inequalities are true.
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.Equal) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.Equal) x x))
(iconst ty (imm64 1))) (iconst ty (imm64 1)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.NotEqual) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.NotEqual) x x))
(iconst ty (imm64 0))) (iconst ty (imm64 0)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.UnsignedGreaterThan) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.UnsignedGreaterThan) x x))
(iconst ty (imm64 0))) (iconst ty (imm64 0)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.UnsignedGreaterThanOrEqual) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.UnsignedGreaterThanOrEqual) x x))
(iconst ty (imm64 1))) (iconst ty (imm64 1)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.SignedGreaterThan) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.SignedGreaterThan) x x))
(iconst ty (imm64 0))) (iconst ty (imm64 0)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.SignedGreaterThanOrEqual) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.SignedGreaterThanOrEqual) x x))
(iconst ty (imm64 1))) (iconst ty (imm64 1)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.UnsignedLessThan) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.UnsignedLessThan) x x))
(iconst ty (imm64 0))) (iconst ty (imm64 0)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.UnsignedLessThanOrEqual) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.UnsignedLessThanOrEqual) x x))
(iconst ty (imm64 1))) (iconst ty (imm64 1)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.SignedLessThan) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.SignedLessThan) x x))
(iconst ty (imm64 0))) (iconst ty (imm64 0)))
(rule (simplify (rule (simplify
(icmp (ty_int ty) (IntCC.SignedLessThanOrEqual) x x)) (icmp (fits_in_64 (ty_int ty)) (IntCC.SignedLessThanOrEqual) x x))
(iconst ty (imm64 1))) (iconst ty (imm64 1)))
;; (x ^ -1) can be replaced with the `bnot` instruction ;; (x ^ -1) can be replaced with the `bnot` instruction