Files
wasmtime/cranelift/codegen/Cargo.toml
Nick Fitzgerald 3a6dd832c0 Harvest left-hand side superoptimization candidates.
Given a clif function, harvest all its integer subexpressions, so that they can
be fed into [Souper](https://github.com/google/souper) as candidates for
superoptimization. For some of these candidates, Souper will successfully
synthesize a right-hand side that is equivalent but has lower cost than the
left-hand side. Then, we can combine these left- and right-hand sides into a
complete optimization, and add it to our peephole passes.

To harvest the expression that produced a given value `x`, we do a post-order
traversal of the dataflow graph starting from `x`. As we do this traversal, we
maintain a map from clif values to their translated Souper values. We stop
traversing when we reach anything that can't be translated into Souper IR: a
memory load, a float-to-int conversion, a block parameter, etc. For values
produced by these instructions, we create a Souper `var`, which is an input
variable to the optimization. For instructions that have a direct mapping into
Souper IR, we get the Souper version of each of its operands and then create the
Souper version of the instruction itself. It should now be clear why we do a
post-order traversal: we need an instruction's translated operands in order to
translate the instruction itself. Once this instruction is translated, we update
the clif-to-souper map with this new translation so that any other instruction
that uses this result as an operand has access to the translated value. When the
traversal is complete we return the translation of `x` as the root of left-hand
side candidate.
2020-09-14 16:27:47 -07:00

96 lines
3.5 KiB
TOML

[package]
authors = ["The Cranelift Project Developers"]
name = "cranelift-codegen"
version = "0.66.0"
description = "Low-level code generator library"
license = "Apache-2.0 WITH LLVM-exception"
documentation = "https://docs.rs/cranelift-codegen"
repository = "https://github.com/bytecodealliance/wasmtime"
categories = ["no-std"]
readme = "README.md"
keywords = ["compile", "compiler", "jit"]
build = "build.rs"
edition = "2018"
[dependencies]
cranelift-codegen-shared = { path = "./shared", version = "0.66.0" }
cranelift-entity = { path = "../entity", version = "0.66.0" }
cranelift-bforest = { path = "../bforest", version = "0.66.0" }
hashbrown = { version = "0.7", optional = true }
target-lexicon = "0.10"
log = { version = "0.4.6", default-features = false }
serde = { version = "1.0.94", features = ["derive"], optional = true }
bincode = { version = "1.2.1", optional = true }
gimli = { version = "0.21.0", default-features = false, features = ["write"], optional = true }
smallvec = { version = "1.0.0" }
thiserror = "1.0.4"
byteorder = { version = "1.3.2", default-features = false }
peepmatic = { path = "../peepmatic", optional = true, version = "0.66.0" }
peepmatic-traits = { path = "../peepmatic/crates/traits", optional = true, version = "0.66.0" }
peepmatic-runtime = { path = "../peepmatic/crates/runtime", optional = true, version = "0.66.0" }
regalloc = "0.0.30"
souper-ir = { version = "1", optional = true }
wast = { version = "22.0.0", optional = true }
# It is a goal of the cranelift-codegen crate to have minimal external dependencies.
# Please don't add any unless they are essential to the task of creating binary
# machine code. Integration tests that need external dependencies can be
# accomodated in `tests`.
[build-dependencies]
cranelift-codegen-meta = { path = "meta", version = "0.66.0" }
[features]
default = ["std", "unwind"]
# The "std" feature enables use of libstd. The "core" feature enables use
# of some minimal std-like replacement libraries. At least one of these two
# features need to be enabled.
std = []
# The "core" features enables use of "hashbrown" since core doesn't have
# a HashMap implementation, and a workaround for Cargo #4866.
core = ["hashbrown"]
# This enables some additional functions useful for writing tests, but which
# can significantly increase the size of the library.
testing_hooks = []
# This enables unwind info generation functionality.
unwind = ["gimli"]
# ISA targets for which we should build.
# If no ISA targets are explicitly enabled, the ISA target for the host machine is enabled.
x86 = []
arm32 = []
arm64 = []
riscv = []
x64 = [] # New work-in-progress codegen backend for x86_64 based on the new isel.
# Option to enable all architectures.
all-arch = [
"x86",
"arm32",
"arm64",
"riscv"
]
# For dependent crates that want to serialize some parts of cranelift
enable-serde = ["serde"]
# Allow snapshotting regalloc test cases. Useful only to report bad register
# allocation failures, or for regalloc.rs developers.
regalloc-snapshot = ["bincode", "regalloc/enable-serde"]
# Recompile our optimizations that are written in the `peepmatic` DSL into a
# compact finite-state transducer automaton.
rebuild-peephole-optimizers = ["peepmatic", "peepmatic-traits", "wast"]
# Enable the use of `peepmatic`-generated peephole optimizers.
enable-peepmatic = ["peepmatic-runtime", "peepmatic-traits", "serde"]
# Enable support for the Souper harvester.
souper-harvest = ["souper-ir", "souper-ir/stringify"]
[badges]
maintenance = { status = "experimental" }