llvm-project.git/llvm/lib/Target/WebAssembly/WebAssemblyFixBrTableDefaults.cpp, branch main

[LLVM] Fix typo "depedent"

2024-07-23T11:52:20+00:00

[WebAssembly] Use SetVector instead of SmallPtrSet in FixBrTableDefaults (#84418)

2024-03-08T17:20:44+00:00

This pass inserts all the MBBs into a set and then iterates over them.
But when
the number of elements gets large enough, SmallPtrSet expands into a
hash table
which wouldn't have a deterministic iteration order since the elements
are
pointers. This results in nondeterministic jump table layouts.
Use SetVector instead for a deterministic iteration order.

[WebAssembly] Create separation between MC and CodeGen layers

2023-08-18T21:08:37+00:00

Move WebAssemblyUtilities from Utils to the CodeGen library. It
primarily deals in MIR layer types, so it really lives in the CodeGen
library.

Move a variety of other things around to try create better separation.

See issue #64166 for more info on layering.

Move llvm/include/CodeGen/WasmAddressSpaces.h back to
llvm/lib/Target/WebAssembly/Utils.

Differential Revision: https://reviews.llvm.org/D156472

[NFC][CodeGen] Rename some functions in MachineInstr.h and remove duplicated comments

2022-03-16T12:25:42+00:00

[WebAssembly] Fix fixBrTableIndex removing instruction without checking uses

2021-11-08T23:53:44+00:00

Fixes: https://bugs.llvm.org/show_bug.cgi?id=52352
Differential Revision: https://reviews.llvm.org/D113230

[WebAssembly] Fixed 64-bit indices in br_table

2020-07-30T17:52:16+00:00

LLVM selection dag assumes "switch" indices are pointer sized, which causes problems for our 32-bit br_table. The new function ensures 32-bit operands don't get unnecessarily extended, and 64-bit operands get truncated.

Note that the changes to the existing test test exactly that: the addition of -NEXT in 2 places ensures no extension is inserted (which the test previously ignored) and that the wrap is present (previously omitted in wasm64 mode).

Differential Revision: https://reviews.llvm.org/D84705

[llvm] Cast to (void) the unused variable.

2020-07-05T10:33:58+00:00

[WebAssembly] Do not assume br_table range checks will be gt_u

2020-07-05T01:11:24+00:00

OSS-Fuzz and the Emscripten test suite uncovered some edge cases in
which the range check instruction seemed to be an (i32.const 0) or
other unexpected instruction, triggering an assertion. Unfortunately
the reproducers are rather complicated, so they don't make good unit
tests. This commit removes the bad assertion and conservatively
optimizes range checks only when the range check instruction is
i32.gt_u.

Differential Revision: https://reviews.llvm.org/D83169

[WebAssembly] Do not omit range checks for i64 switches

2020-07-04T00:15:39+00:00

Summary:
Since the br_table instruction takes an i32, switches over i64s (and
larger integers) must use the i32.wrap_i64 instruction to truncate the
table index. This truncation makes numbers just over 2^32
indistinguishable from small numbers, so it was a miscompilation to
omit the range check preceding these br_tables. This change fixes the
problem by skipping the "fixing" of the br_table when the range check
is an i64 instruction.

Fixes PR46447.

Reviewers: aheejin, dschuff, kripken

Reviewed By: kripken

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83017

[WebAssembly] Fix bug in FixBrTables and use branch analysis utils

2020-06-17T19:34:45+00:00

Summary:
This commit fixes a bug in the FixBrTables pass in which an
unconditional branch from the switch header block to the jump table
block was not removed before the blocks were combined. The result was
an invalid CFG in the MachineFunction. This commit also switches from
using bespoke branch analysis and deletion code to using the standard
utilities for the same.

Reviewers: aheejin, dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81909