Commit Graph

42 Commits

Author SHA1 Message Date
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
David Blaikie 2110924909 Fix WebAssembly backend for some LLVM API changes
llvm-svn: 320893
2017-12-15 23:52:06 +00:00
Sam Clegg 9d24fb7ff3 [WebAssembly] Use __stack_pointer global when writing wasm binary
This ensures that symbolic relocations are generated for stack
pointer manipulations.

These relocations are of type R_WEBASSEMBLY_GLOBAL_INDEX_LEB.
This change also adds support for reading relocations of this
type in WasmObjectFile.cpp.

Since its a globally imported symbol this does mean that
the get_global/set_global instruction won't be valid until
the objects are linked that global used in no longer an
imported global.

Differential Revision: https://reviews.llvm.org/D34172

llvm-svn: 305616
2017-06-16 23:59:10 +00:00
Dan Gohman 970d02c42d [WebAssembly] Initial linking metadata support
Add support for the new relocations and linking metadata section support in
https://github.com/WebAssembly/tool-conventions/blob/master/Linking.md. In
particular, this allows LLVM to indicate which variable is the stack pointer,
so that it can be linked with other objects.

This also adds support for emitting type relocations for call_indirect
instructions.

Right now, this is mainly tested by using wabt and hexdump to examine the
output on selected testcases. We'll add more tests as the design stablizes
and more of the pieces are in place.

llvm-svn: 299141
2017-03-30 23:58:19 +00:00
Dan Gohman 82607f56bd [WebAssembly] Add support for using a wasm global for the stack pointer.
This replaces the __stack_pointer variable which was allocated in linear
memory.

llvm-svn: 296201
2017-02-24 23:46:05 +00:00
Dan Gohman d934cb8806 [WebAssembly] Basic support for Wasm object file encoding.
With the "wasm32-unknown-unknown-wasm" triple, this allows writing out
simple wasm object files, and is another step in a larger series toward
migrating from ELF to general wasm object support. Note that this code
and the binary format itself is still experimental.

llvm-svn: 296190
2017-02-24 23:18:00 +00:00
Dan Gohman f295cc8fb5 [WebAssembly] Fix a compiler warning. NFC.
Fix a warning about a comparison between signed and unsigned integer
expressions.

llvm-svn: 288532
2016-12-02 20:13:05 +00:00
Derek Schuff 0d41b7b3f3 [WebAssembly] Emit a BasePointer when we have overly-aligned stack objects
Because we shift the stack pointer by an unknown amount, we need an
additional pointer. In the case where we have variable-size objects
as well, we can't reuse the frame pointer, thus three pointers.

Patch by Jacob Gravelle

Differential Revision: https://reviews.llvm.org/D26263

llvm-svn: 286160
2016-11-07 22:00:48 +00:00
Dan Gohman 48abaa9c74 [WebAssembly] Reorder load/store operands to match binary encoding.
The p2align operand of a load/store is encoded before the offset
operand; reorder the MachineInstr operands accordingly.

llvm-svn: 285044
2016-10-25 00:17:11 +00:00
Dan Gohman 7f1bdb2e02 [WebAssembly] Remove the output operand from stores.
Per spec changes, store instructions in WebAssembly no longer have a return
value. Update the instruction descriptions.

Differential Revision: https://reviews.llvm.org/D25122

llvm-svn: 283501
2016-10-06 22:08:28 +00:00
Benjamin Kramer 9bc1b230fd [WebAssembly] Plug MachineMemOperand leaks.
llvm-svn: 278545
2016-08-12 18:33:50 +00:00
Matthias Braun 941a705b7b MachineFunction: Return reference for getFrameInfo(); NFC
getFrameInfo() never returns nullptr so we should use a reference
instead of a pointer.

llvm-svn: 277017
2016-07-28 18:40:00 +00:00
Benjamin Kramer bdc4956bac Pass DebugLoc and SDLoc by const ref.
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.

llvm-svn: 272512
2016-06-12 15:39:02 +00:00
Dan Gohman d530f68d45 [WebAssembly] Put __stack_pointer in the offset field of loads and stores.
Instead of this:

i32.const       $push10=, __stack_pointer
i32.load        $push11=, 0($pop10)

Emit this:

i32.const       $push10=, 0
i32.load        $push11=, __stack_pointer($pop10)

It's not currently clear which is better, though there's a chance the second
form may be better at overall compression. We can revisit this when we have
more data; for now it makes sense to make PEI consistent with isel.

Differential Revision: http://reviews.llvm.org/D20411

llvm-svn: 270635
2016-05-24 23:47:41 +00:00
Dan Gohman 7100809080 [WebAssembly] Rename $discard to $drop in the assembly output.
llvm-svn: 269862
2016-05-17 23:19:03 +00:00
Dan Gohman d08cd15f33 [WebAssembly] Don't stackify calls past stack pointer modifications.
llvm-svn: 269843
2016-05-17 21:14:26 +00:00
Dan Gohman 0cfb5f852d [WebAssembly] Move register stackification and coloring to a late phase.
Move the register stackification and coloring passes to run very late, after
PEI, tail duplication, and most other passes. This means that all code emitted
and expanded by those passes is now exposed to these passes. This also
eliminates the need for prologue/epilogue code to be manually stackified,
which significantly simplifies the code.

This does require running LiveIntervals a second time. It's useful to think
of these late passes not as late optimization passes, but as a domain-specific
compression algorithm based on knowledge of liveness information. It's used to
compress the code after all conventional optimizations are complete, which is
why it uses LiveIntervals at a phase when actual optimization passes don't
typically need it.

Differential Revision: http://reviews.llvm.org/D20075

llvm-svn: 269012
2016-05-10 04:24:02 +00:00
Dan Gohman 450a80754f [WebAssembly] Don't emit epilogue code in the middle of stackified code.
llvm-svn: 268679
2016-05-05 20:41:15 +00:00
Hans Wennborg e1a2e90ffa Change eliminateCallFramePseudoInstr() to return an iterator
This will become necessary in a subsequent change to make this method
merge adjacent stack adjustments, i.e. it might erase the previous
and/or next instruction.

It also greatly simplifies the calls to this function from Prolog-
EpilogInserter. Previously, that had a bunch of logic to resume iteration
after the call; now it just continues with the returned iterator.

Note that this changes the behaviour of PEI a little. Previously,
it attempted to re-visit the new instruction created by
eliminateCallFramePseudoInstr(). That code was added in r36625,
but I can't see any reason for it: the new instructions will obviously
not be pseudo instructions, they will not have FrameIndex operands,
and we have already accounted for the stack adjustment.

Differential Revision: http://reviews.llvm.org/D18627

llvm-svn: 265036
2016-03-31 18:33:38 +00:00
Derek Schuff d4207ba0f6 [WebAssembly] Stackify code emitted by eliminateFrameIndex and SP writeback
Summary:
MRI::eliminateFrameIndex can emit several instructions to do address
calculations; these can usually be stackified. Because instructions with
FI operands can have subsequent operands which may be expression trees,
find the top of the leftmost tree and insert the code before it, to keep
the LIFO property.

Also use stackified registers when writing back the SP value to memory
in the epilog; it's unnecessary because SP will not be used after the
epilog, and it results in better code.

Differential Revision: http://reviews.llvm.org/D18234

llvm-svn: 263725
2016-03-17 17:00:29 +00:00
Derek Schuff 4b3bb213b2 [WebAssembly] Implement red zone for user stack
Implements a mostly-conventional redzone for the userspace
stack. Because we have unsigned load/store offsets we continue to use a
local SP subtracted from the incoming SP but do not write it back to
memory.

Differential Revision: http://reviews.llvm.org/D17525

llvm-svn: 261662
2016-02-23 18:13:07 +00:00
Derek Schuff 27e3b8a6e3 [WebAssembly] Fix writeback of stack pointer with dynamic alloca
Previously the stack pointer was only written back to memory in the
prolog. But this is wrong for dynamic allocas, for which
target-independent codegen handles SP updates after the prolog (and
possibly even in another BB). Instead update the SP global in
ADJCALLSTACKDOWN which is generated after the SP update sequence.
This will have further refinements when we add red zone support.

llvm-svn: 261579
2016-02-22 21:57:17 +00:00
Derek Schuff 90dbb8cfc3 [WebAssembly] Write stack pointer back to memory when FP is used
The stack pointer is bumped when there is a frame pointer or when there
are static-size objects, but was only getting written back when there
were static-size objects.

llvm-svn: 261453
2016-02-20 22:18:47 +00:00
Derek Schuff dc5f6aa4bb [WebAssembly] Stackify function prologs and epilogs
The instructions are the same, but fewer locals are used.

Differential Revision: http://reviews.llvm.org/D17428

llvm-svn: 261452
2016-02-20 21:46:50 +00:00
Dan Gohman 94c6566055 [WebAssembly] Implement __builtin_frame_address.
Differential Revision: http://reviews.llvm.org/D17307

llvm-svn: 261032
2016-02-16 23:48:04 +00:00
Derek Schuff 3f0632958b [WebAssembly] Reformat WebAssemblyFrameLowering and WebAssemblyISelLowering
Reviewers: sunfish, jfb

Subscribers: jfb, dschuff

Differential Revision: http://reviews.llvm.org/D17156

llvm-svn: 260585
2016-02-11 20:57:09 +00:00
Derek Schuff 992d83fd0d [WebAssembly] Address comments left over from r260421
llvm-svn: 260429
2016-02-10 20:14:15 +00:00
Derek Schuff 27501e2065 [WebAssembly] Switch varags calling convention to use a register
Instead of passing varargs directly on the user stack, allocate a buffer in
the caller's stack frame and pass a pointer to it. This simplifies the C
ABI (e.g. non-C callers of C functions do not need to use C's user stack if
they have their own mechanism) and allows further optimizations in the future
(e.g. fewer functions may need to use the stack).

Differential Revision: http://reviews.llvm.org/D17048

llvm-svn: 260421
2016-02-10 19:51:04 +00:00
JF Bastien 3ca3ea690f WebAssembly NFC: fix build warning
WebAssemblyFrameLowering.cpp:158:44: warning: enumeral and non-enumeral type in conditional expression [enabled by default]

llvm-svn: 259303
2016-01-30 11:19:26 +00:00
Derek Schuff 6ea637af35 [WebAssembly] Support frame pointer
Add support for frame pointer use in prolog/epilog.
Supports dynamic allocas but not yet over-aligned locals.
Target-independend CG generates SP updates, but we still need to write
back the SP value to memory when necessary.

llvm-svn: 259220
2016-01-29 18:37:49 +00:00
Derek Schuff 90d9e8d370 [WebAssembly] Omit no-op adds for non-mem uses of FrameIndex
Differential Revision: http://reviews.llvm.org/D16554

llvm-svn: 258872
2016-01-26 22:47:43 +00:00
Dan Gohman bb3722430f [WebAssembly] Implement unaligned loads and stores.
Differential Revision: http://reviews.llvm.org/D16534

llvm-svn: 258779
2016-01-26 03:39:31 +00:00
Dan Gohman 3196650bf3 [WebAssembly] Use the templated form of MachineFunction::getSubtarget(). NFC.
llvm-svn: 258126
2016-01-19 14:53:19 +00:00
Derek Schuff 8bb5f2927a [WebAssembly] Implement eliminateCallFramePseudo
Summary:
Implement eliminateCallFramePsuedo to handle ADJCALLSTACKUP/DOWN
pseudo-instructions. Add a test calling a vararg function which causes non-0
adjustments. This revealed an issue with RegisterCoalescer wherein it
eliminates a COPY from SP32 to a vreg but failes to update the live ranges
of EXPR_STACK, causing a machineinstr verifier failure (so this test
is commented out).

Also add a dynamic alloca test, which causes a callseq_end dag node with
a 0 (instead of undef) second argument to be generated. We currently fail to
select that, so adjust the ADJCALLSTACKUP tablegen code to handle it.

Differential Revision: http://reviews.llvm.org/D15587

llvm-svn: 255844
2015-12-16 23:21:30 +00:00
Derek Schuff 9769debf88 [WebAssembly] Implement prolog/epilog insertion and FrameIndex elimination
Summary:
Use the SP32 physical register as the base for FrameIndex
lowering. Update it and the __stack_pointer global var in the prolog and
epilog. Extend the mapping of virtual registers to wasm locals to
include the physical registers.

Rather than modify the target-independent PrologEpilogInserter (which
asserts that there are no virtual registers left) include a
slightly-modified copy for Wasm that does not have this assertion and
only clears the virtual registers if scavenging was needed (which of
course it isn't for wasm).

Differential Revision: http://reviews.llvm.org/D15344

llvm-svn: 255392
2015-12-11 23:49:46 +00:00
Dan Gohman 7a6b9825ce [WebAssembly] Minor clang-format and selected clang-tidy cleanups. NFC.
llvm-svn: 254267
2015-11-29 22:32:02 +00:00
Dan Gohman 9c54d3b4c6 [WebAssembly] Clean up several FIXME comments.
llvm-svn: 254079
2015-11-25 18:13:18 +00:00
Dan Gohman e419a7c307 [WebAssembly] Use the checked form of MachineFunction::getSubtarget. NFC.
llvm-svn: 245852
2015-08-24 16:46:31 +00:00
JF Bastien b9073fb20a WebAssembly: basic bitcode → assembly CodeGen test
Summary:
Add a basic CodeGen bitcode test which (for now) only prints out the function name and nothing else. The current code merely implements the basic needed for the test run to not crash / assert. Getting to that point required:

 - Basic InstPrinter.
 - Basic AsmPrinter.
 - DiagnosticInfoUnsupported (not strictly required, but nice to have, duplicated from AMDGPU/BPF's ISelLowering).
 - Some SP and register setup in WebAssemblyTargetLowering.
 - Basic LowerFormalArguments.
 - GenInstrInfo.
 - Placeholder LowerFormalArguments.
 - Placeholder CanLowerReturn and LowerReturn.
 - Basic DAGToDAGISel::Select, which requiresGenDAGISel.inc as well as GET_INSTRINFO_ENUM with GenInstrInfo.inc.
 - Remove WebAssemblyFrameLowering::determineCalleeSaves and rely on default.
 - Implement WebAssemblyFrameLowering::hasFP, same as AArch64's implementation.

Follow-up patches will implement a real AsmPrinter, which will require adding MI opcodes specific to WebAssembly.

Reviewers: sunfish

Subscribers: aemerson, jfb, llvm-commits

Differential Revision: http://reviews.llvm.org/D11369

llvm-svn: 242939
2015-07-22 21:28:15 +00:00
JF Bastien c8f48c19d3 WebAssembly: fix build breakage.
Summary:
processFunctionBeforeCalleeSavedScan was renamed to determineCalleeSaves and now takes a BitVector parameter as of rL242165, reviewed in http://reviews.llvm.org/D10909

WebAssembly is still marked as experimental and therefore doesn't build by default. It does, however, grep by default! I notice that processFunctionBeforeCalleeSavedScan is still mentioned in a few comments and error messages, which I also fixed.

Reviewers: qcolombet, sunfish

Subscribers: jfb, dsanders, hfinkel, MatzeB, llvm-commits

Differential Revision: http://reviews.llvm.org/D11199

llvm-svn: 242242
2015-07-14 23:06:07 +00:00
JF Bastien 03855df197 WebAssembly: start instructions
Summary:
* Add 64-bit address space feature.
* Rename SIMD feature to SIMD128.
* Handle single-thread model with an IR pass (same way ARM does).
* Rename generic processor to MVP, to follow design's lead.
* Add bleeding-edge processors, with all features included.
* Fix a few DEBUG_TYPE to match other backends.

Test Plan: ninja check

Reviewers: sunfish

Subscribers: jfb, llvm-commits

Differential Revision: http://reviews.llvm.org/D10880

llvm-svn: 241211
2015-07-01 23:41:25 +00:00
Dan Gohman 10e730a263 [WebAssembly] Initial WebAssembly backend
This WebAssembly backend is just a skeleton at this time and is not yet
functional.

llvm-svn: 241022
2015-06-29 23:51:55 +00:00