Commit Graph

9 Commits

Author SHA1 Message Date
Dan Gohman b7c2400fa7 [WebAssembly] Optimize away return instructions using fallthroughs.
This saves a small amount of code size, and is a first small step toward
passing values on the stack across block boundaries.

Differential Review: http://reviews.llvm.org/D20450

llvm-svn: 270294
2016-05-21 00:21:56 +00:00
Dan Gohman b6fd39a3a7 [WebAssembly] Rematerialize constants rather than hold them live in registers.
Teach the register stackifier to rematerialize constants that have multiple
uses instead of leaving them in registers. In the WebAssembly encoding, it's
the same code size to materialize most constants as it is to read a value
from a register.

llvm-svn: 258142
2016-01-19 16:59:23 +00:00
Dan Gohman 26c6765bd6 [WebAssembly] Define WebAssembly-specific relocation codes.
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.

llvm-svn: 257416
2016-01-11 23:38:05 +00:00
Dan Gohman 0c6f5ac50a [WebAssembly] Add -m:e to the target triple.
This enables ELF-style name mangling, which primarily means using ".L" for
private symbols.

llvm-svn: 257020
2016-01-07 03:19:23 +00:00
Dan Gohman 1270b0a91d [WebAssembly] Make several tests more strict.
llvm-svn: 254077
2015-11-25 17:33:15 +00:00
Dan Gohman 2f16f25391 [WebAssembly] Don't special-case call operand order.
With the '=' suffix now indicating which operands are output operands, it's
no longer as important to distinguish between a call's inputs and its outputs
using operand ordering, so we can go back to printing them in the normal order.

llvm-svn: 253925
2015-11-23 22:04:06 +00:00
Dan Gohman 700515fa92 [WebAssembly] Suffix output operands with '='.
This distinguishes input operands from output operands. This is something of
a syntactic experiment to see whether the mild amount of clutter this adds is
outweighed by the extra information it conveys to the reader.

llvm-svn: 253922
2015-11-23 21:55:57 +00:00
Dan Gohman 4ba4816b97 [WebAssembly] Enable register coloring and register stackifying.
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.

llvm-svn: 253465
2015-11-18 16:12:01 +00:00
Dan Gohman 8ad045c1d1 [WebAssembly] Support signext, zeroext, and several other function attributes.
llvm-svn: 253148
2015-11-14 23:15:41 +00:00