Commit Graph

6 Commits

Author SHA1 Message Date
Thomas Lively 122b0220fd [WebAssembly] Remove datalayout strings from llc tests
The data layout strings do not have any effect on llc tests and will become
misleadingly out of date as we continue to update the canonical data layout, so
remove them from the tests.

Differential Revision: https://reviews.llvm.org/D105842
2021-07-14 11:17:08 -07:00
Thomas Lively 7f50c15be5 Reland "[WebAssembly] Eliminate range checks on br_tables"
This reverts commit 755a895915.
Although I was not able to reproduce any test failures locally,
aheejin was able to reproduce them and found a fix, applied here.
2020-06-03 14:04:59 -07:00
Thomas Lively 755a895915 Revert "[WebAssembly] Eliminate range checks on br_tables"
This reverts commit f99d5f8c32.
The change was causing UBSan and other failures on some bots.
2020-06-03 01:26:53 -07:00
Thomas Lively f99d5f8c32 [WebAssembly] Eliminate range checks on br_tables
Summary:
Jump tables for most targets cannot handle out of range indices by
themselves, so LLVM emits range checks to guard the jump
tables. WebAssembly, on the other hand, implements jump tables using
the br_table instruction, which takes a default branch target as an
operand, making the range checks redundant. This patch introduces a
new MachineFunction pass in the WebAssembly backend to find and
eliminate the redundant range checks.

Reviewers: aheejin, dschuff

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80863
2020-06-02 13:14:27 -07:00
Wouter van Oortmerssen d3c544aa6e [WebAssembly] Fix assembler parsing of br_table.
Summary:
We use `variable_ops` in the tablegen defs to denote the list of
branch targets in `br_table`, but unlike other uses of `variable_ops`
(e.g. call) the these branch targets need to actually be encoded in the
instruction. The existing tables for `variable_ops` cause not operands
to be accepted by the assembly matcher.

Following the example of ARM:
2cc0a7da87/lib/Target/ARM/ARMInstrInfo.td (L550-L555)
we introduce a new operand type to capture this list, and we use the
same {} syntax as ARM as well to differentiate them from regular
integer operands.

Also removed definition and use of TSFlags in tablegen defs, since
`br_table` now has a non-variable_ops immediate operand, so the
previous logic of only the variable_ops arguments being labels didn't
make sense anymore.

Reviewers: dschuff, aheejin, sunfish

Subscribers: javed.absar, sbc100, jgravelle-google, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D55401

llvm-svn: 349405
2018-12-17 22:04:44 +00:00
Heejin Ahn a40303aa03 [WebAssembly] Fix assembly printing of br_table
Summary: In `br_table's stack version asm string, \t was missing.

Reviewers: aardappel

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

Differential Revision: https://reviews.llvm.org/D53516

llvm-svn: 344981
2018-10-23 00:28:14 +00:00