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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299141 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296190 91177308-0d34-0410-b5e6-96231b3b80d8
Support a new assembler directive, .import_global, to declare imported
global variables (i.e. those with external linkage and no
initializer). The linker turns these into wasm imports.
Patch by Jacob Gravelle
Differential Revision: https://reviews.llvm.org/D26875
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288296 91177308-0d34-0410-b5e6-96231b3b80d8
This changes locals from being declared by the emitLocal hook in
WebAssemblyTargetStreamer, rather than with an instruction. After exploring
the infastructure in LLVM more, this seems to make more sense since
declaring locals doesn't use an encoded opcode.
This also adds more 0xd opcodes, type encodings, and miscellaneous
binary encoding bits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285040 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This patch implements CFI for WebAssembly. It modifies the
LowerTypeTest pass to pre-assign table indexes to functions that are
called indirectly, and lowers type checks to test against the
appropriate table indexes. It also modifies the WebAssembly backend to
support a special ".indidx" assembly directive that propagates the table
index assignments out to the linker.
Patch by Dominic Chen
Differential Revision: https://reviews.llvm.org/D21768
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277398 91177308-0d34-0410-b5e6-96231b3b80d8
Under emscripten, C code can take the address of a function implemented
in Javascript (which is exposed via an import in wasm). Because imports
do not have linear memory address in wasm, we need to generate a thunk
to be the target of the indirect call; it call the import directly.
To make this possible, LLVM needs to emit the type signatures for these
functions, because they may not be called directly or referred to other
than where the address is taken.
This uses s new .s directive (.functype) which specifies the signature.
Differential Revision: http://reviews.llvm.org/D20891
Re-apply r271599 but instead of bailing with an error when a declared
function has multiple returns, replace it with a pointer argument. Also
add the test case I forgot to 'git add' last time around.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271703 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts r271599, it broke the integration tests.
More places than I expected had nontrival return types in imports, or
else the check was wrong.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271606 91177308-0d34-0410-b5e6-96231b3b80d8
Under emscripten, C code can take the address of a function implemented
in Javascript (which is exposed via an import in wasm). Because imports
do not have linear memory address in wasm, we need to generate a thunk
to be the target of the indirect call; it call the import directly.
To make this possible, LLVM needs to emit the type signatures for these
functions, because they may not be called directly or referred to other
than where the address is taken.
This uses s new .s directive (.functype) which specifies the signature.
Differential Revision: http://reviews.llvm.org/D20891
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271599 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269012 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor .param, .result, .local, and .endfunc, as directives, using the
proper MCTargetStreamer mechanism, rather than fake instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257511 91177308-0d34-0410-b5e6-96231b3b80d8
This patch changes the way labels are referenced. Instead of referencing the
basic-block label name (eg. .LBB0_0), instructions now just have an immediate
which indicates the depth in the control-flow stack to find a label to jump to.
This makes them much closer to what we expect to have in the binary encoding,
and avoids the problem of basic-block label names not being explicit in the
binary encoding.
Also, it terminates blocks and loops with end_block and end_loop instructions,
rather than basic-block label names, for similar reasons.
This will also fix problems where two constructs appear to have the same label,
because we no longer explicitly use labels, so consumers that need labels will
presumably create their own labels, and presumably they won't reuse labels
when they do.
This patch does make the code a little more awkward to read; as a partial
mitigation, this patch also introduces comments showing where the labels are,
and comments on each branch showing where it's branching to.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257505 91177308-0d34-0410-b5e6-96231b3b80d8
Currently WebAssembly has two kinds of relocations; data addresses and
function addresses. This adds ELF relocations for them, as well as an
MC symbol kind to indicate which type of relocation is needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257416 91177308-0d34-0410-b5e6-96231b3b80d8
WebAssembly is currently using labels to end scopes, so for example a
loop scope looks like this:
BB0_0:
loop BB0_1
...
BB0_1:
with BB0_0 being the label of the first block not in the loop. This
requires that the label be printed even when it's only reachable via
fallthrough. To arrange this, insert a no-op LOOP_END instruction in
such cases at the end of the loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253901 91177308-0d34-0410-b5e6-96231b3b80d8
WebAssembly does not have physical registers, so even if LLVM uses physical
registers like SP, they'll need to be lowered to virtual registers before
AsmPrinter time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253644 91177308-0d34-0410-b5e6-96231b3b80d8
This also takes the push/pop syntax another step forward, introducing stack
slot numbers to make it easier to see how expressions are connected. For
example, the value pushed in $push7 is popped in $pop7.
And, this begins an experiment with making get_local and set_local implicit
when an operation directly uses or defines a register. This greatly reduces
clutter. If this experiment succeeds, it may make sense to do this for
const instructions as well.
And, this introduces more special code for ARGUMENTS; hopefully this code
will soon be obviated by proper support for live-in virtual registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253465 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Previously return type information for a function was derived from
return dag nodes. But this didn't work for dags with != return node. So
instead compute it directly from the LLVM function as is done for imports.
Differential Revision: http://reviews.llvm.org/D14593
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253251 91177308-0d34-0410-b5e6-96231b3b80d8
Switch to MC for instruction printing.
This encompasses several changes which are all interconnected:
- Use the MC framework for printing almost all instructions.
- AsmStrings are now live.
- This introduces an indirection between LLVM vregs and WebAssembly registers,
and a new pass, WebAssemblyRegNumbering, for computing a basic the mapping.
This addresses some basic issues with argument registers and unused registers.
- The way ARGUMENT instructions are handled no longer generates redundant
get_local+set_local for every argument.
This also changes the assembly syntax somewhat; most notably, MC's printing
does not use sigils on label names, so those are no longer present, and
push/pop now have a sigil to keep them unambiguous.
The usage of set_local/get_local/$push/$pop will continue to evolve
significantly. This patch is just one step of a larger change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252910 91177308-0d34-0410-b5e6-96231b3b80d8
This encompasses several changes which are all interconnected:
- Use the MC framework for printing almost all instructions.
- AsmStrings are now live.
- This introduces an indirection between LLVM vregs and WebAssembly registers,
and a new pass, WebAssemblyRegNumbering, for computing a basic the mapping.
This addresses some basic issues with argument registers and unused registers.
- The way ARGUMENT instructions are handled no longer generates redundant
get_local+set_local for every argument.
This also changes the assembly syntax somewhat; most notably, MC's printing
use sigils on label names, so those are no longer present, and push/pop now
have a sigil to keep them unambiguous.
The usage of set_local/get_local/$push/$pop will continue to evolve
significantly. This patch is just one step of a larger change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252858 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Conversion opcode name format should be f64.convert_u/i64 not f64_convert_u
Author: s3ththompson
Reviewers: jfb
Subscribers: sunfish, jfb, llvm-commits, dschuff
Differential Revision: http://reviews.llvm.org/D14160
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251613 91177308-0d34-0410-b5e6-96231b3b80d8
