As a follow-up to #5780, disassemble the regions identified by bb_starts, falling back on disassembling the whole buffer. This ensures that instructions like br_table that introduce a lot of constants don't throw off capstone for the remainder of the function.
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Co-authored-by: Jamey Sharp <jamey@minilop.net>
* cranelift: Add `adrp` encoding to AArch64 backend
* cranelift: Support GOT Symbol References in AArch64
* cranelift: Add MachO GOT relocations
* cranelift: Do not mark the GOT PageOffset12 MachO relocation as relative
This updates the signatures of the `xmm_rm_r` helper function and then
updates existing users and migrates other users to the helper now that
the type information is no longer required.
* Add (bnot (bxor x y)) lowerings for s390x/aarch64
I originally thought that s390x's original lowering in #5709, but as was
rightfully pointed out `(bnot (bxor x y))` is equivalent to
`(bxor x (bnot y))` so the special lowering for one should apply as a
special lowering for the other. For the s390x and aarch64 backend that
have already have a fused lowering of the bxor/bnot add a lowering
additionally for the bnot/bxor combination.
* Add bnot(bxor(..)) tests for s390x 128-bit sizes
As jump tables are used by at most one br_table instruction, inline their definition in those instructions instead of requiring them to be declared as function-level metadata.
Move the storage for jump tables off of FunctionStencil and onto DataFlowGraph. This change is in service of #5731, making it easier to access the jump table data in the context of helpers like inst_values.
* Generalize `n ^ !n` optimization to more types
* Generalize `x & -1` optimization to more types
Also mark the `x & x` rewrite to `subsume`.
* Cranelift: Optimize x|!x and x&!x to constants
These cases are much like the existing x^!x rules.
Similar to when we exposed the DataFlowGraph::insts field through a restrictive newtype, expose DataFlowGraph::blocks through an interface that allows a restrictive set of operations. This field being public now allows us to avoid a rematch in ssa construction, and simplifies the implementation of adding a block argument to a block referenced by a br_table instruction.
We don't need to spend time going through the GVN map to dedup a
newly-constructed `iconst 0` when we already matched that value on the
left-hand side of these rules.
Also, mark these rules as subsuming any others since we can't do better
than reducing an expression to a constant.
I was playing around with souper recently on some wasms I had lying
around and these are some optimization opportunities that popped out
which seemed easy-enough to add to the egraph-based optimizations.
When investigating #5716, I found that rematerialization of a `call`, in
addition to blowing up for other reasons, caused aliasing of the varargs
list (the `EntityList` in the `ListPool`), such that editing the args of
the second copy of the call instruction inadvertently updated the first
as well.
This PR modifies `DataFlowGraph::clone_inst` so that it always clones
the varargs list if present. This shouldn't have any functional impact
on Cranelift today, because we don't rematerialize any instructions with
varargs; but it's important to get it right to avoid a bug later!
We don't have overlap in behavior for branch instructions anymore, so we can remove analyze_branch and instead match on the InstructionData directly.
Co-authored-by: Jamey Sharp <jamey@minilop.net>
In the provided test case in #5716, the result of a call was then
added to 0. We have a rewrite rule that sets the remat-bit on any add
of a value and a constant, because these frequently appear (e.g. from
address offset calculations) and this can frequently reduce register
pressure (one long-lived base vs. many long-lived base+offset values).
Separately, we have an algebraic rule that `x+0` rewrites to `x`.
The result of this was that we had an eclass with the remat bit set on
the add, but the add was also union'd into the call. We pick the
latter during extraction, because it's cheaper not to do the add at
all; but we still get the remat bit, and try to remat a call (!),
which blows up later.
This PR fixes the logic to look up the "best value" for a value (i.e.,
whatever extraction determined), and look up the remat bit on *that*
node, not the canonical node.
(Why did the canonical node become the iadd and not the call? Because
the former had a lower value-number, as an accident of IR
construction; we don't impose any requirements on the input CLIF's
value-number ordering, and I don't think this breaks any of the
important acyclic properties, even though there is technically a
dependence from a lower-numbered to a higher-numbered node. In essence
one can think of them as having "virtual numbers" in any true
topologically-sorted order, and the only place the actual integer
indices matter should be in choosing the "canonical ID", which is just
used for dedup'ing, modulo this bug.)
Fixes#5716.
Instead of identifying unused branch tables by looking for unused blocks inside of them, track used branch tables while traversing reachable blocks. This introduces an extra allocation of an EntitySet to track the used jump tables, but as those are few and this function runs once per ir::Function, the allocation seems reasonable.
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.
* Remove trailing whitespace in `lower.isle` files
* Legalize the `band_not` instruction into simpler form
This commit legalizes the `band_not` instruction into `band`-of-`bnot`,
or two instructions. This is intended to assist with egraph-based
optimizations where the `band_not` instruction doesn't have to be
specifically included in other bit-operation-patterns.
Lowerings of the `band_not` instruction have been moved to a
specialization of the `band` instruction.
* Legalize `bor_not` into components
Same as prior commit, but for the `bor_not` instruction.
* Legalize bxor_not into bxor-of-bnot
Same as prior commits. I think this also ended up fixing a bug in the
s390x backend where `bxor_not x y` was actually translated as `bnot
(bxor x y)` by accident given the test update changes.
* Simplify not-fused operands for riscv64
Looks like some delegated-to rules have special-cases for "if this
feature is enabled use the fused instruction" so move the clause for
testing the feature up to the lowering phase to help trigger other rules
if the feature isn't enabled. This should make the riscv64 backend more
consistent with how other backends are implemented.
* Remove B{and,or,xor}Not from cost of egraph metrics
These shouldn't ever reach egraphs now that they're legalized away.
* Add an egraph optimization for `x^-1 => ~x`
This adds a simplification node to translate xor-against-minus-1 to a
`bnot` instruction. This helps trigger various other optimizations in
the egraph implementation and also various backend lowering rules for
instructions. This is chiefly useful as wasm doesn't have a `bnot`
equivalent, so it's encoded as `x^-1`.
* Add a wasm test for end-to-end bitwise lowerings
Test that end-to-end various optimizations are being applied for input
wasm modules.
* Specifically don't self-update rustup on CI
I forget why this was here originally, but this is failing on Windows
CI. In general there's no need to update rustup, so leave it as-is.
* Cleanup some aarch64 lowering rules
Previously a 32/64 split was necessary due to the `ALUOp` being different
but that's been refactored away no so there's no longer any need for
duplicate rules.
* Narrow a x64 lowering rule
This previously made more sense when it was `band_not` and rarely used,
but be more specific in the type-filter on this rule that it's only
applicable to SIMD types with lanes.
* Simplify xor-against-minus-1 rule
No need to have the commutative version since constants are already
shuffled right for egraphs
* Optimize band-of-bnot when bnot is on the left
Use some more rules in the egraph algebraic optimizations to
canonicalize band/bor/bxor with a `bnot` operand to put the operand on
the right. That way the lowerings in the backends only have to list the
rule once, with the operand on the right, to optimize both styles of
input.
* Add commutative lowering rules
* Update cranelift/codegen/src/isa/x64/lower.isle
Co-authored-by: Jamey Sharp <jamey@minilop.net>
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Co-authored-by: Jamey Sharp <jamey@minilop.net>
Also move these optimization rules to cprop.isle; it's where all the
other similar rules are.
Like the other cprop rules, these can subsume any other rules. We can't
do better than reducing an expression to a constant.
The new i64_sextend_imm64 and u64_uextend_imm64 constructors are useful
helpers to clean up other code. I applied them to `imm64_icmp` while I
was here, as well as using the existing `ty_mask` helper to clean up
`imm64_masked`.
* Cranelift: Introduce the `tail` calling convention
This is an unstable-ABI calling convention that we will eventually use to
support Wasm tail calls.
Co-Authored-By: Jamey Sharp <jsharp@fastly.com>
* Cranelift: Introduce the `return_call` and `return_call_indirect` instructions
These will be used to implement tail calls for Wasm and any other language
targeting CLIF. The `return_call_indirect` instruction differs from the Wasm
instruction of the same name by taking a native address callee rather than a
Wasm function index.
Co-Authored-By: Jamey Sharp <jsharp@fastly.com>
* Cranelift: Implement verification rules for `return_call[_indirect]`
They must:
* have the same return types between the caller and callee,
* have the same calling convention between caller and callee,
* and that calling convention must support tail calls.
Co-Authored-By: Jamey Sharp <jsharp@fastly.com>
* cargo fmt
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Co-authored-by: Jamey Sharp <jsharp@fastly.com>
This rewrite was introduced in #5676 and then reverted in #5682 due to a footgun
where we accidentally weren't actually checking the `y == !z` precondition. This
commit fixes the precondition check. It also fixes the arithmetic to be
correctly masked to the value type's width.
This reverts commit 268f6bfc1d.
Add a display method to BlockCall that returns a std::fmt::Displayable result. Rework the display code in the write module of cranelift-codegen to use this method instead.
