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
A request has been made to the official registry, but an official value is
not yet available. This patch uses a temporary value in order to support
development. When an official value is recieved, the value of EM_WEBASSEMBLY
will be updated.
llvm-svn: 257517
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
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 $pop7.
And, this begins an experiment with making get_local and set_local implicit
when an operation directly uses or defines a register. This greatly reduces
clutter. If this experiment succeeds, it may make sense to do this for
const instructions as well.
And, this introduces more special code for ARGUMENTS; hopefully this code
will soon be obviated by proper support for live-in virtual registers.
llvm-svn: 253465
Summary:
Previously return type information for a function was derived from
return dag nodes. But this didn't work for dags with != return node. So
instead compute it directly from the LLVM function as is done for imports.
Differential Revision: http://reviews.llvm.org/D14593
llvm-svn: 253251
Switch to MC for instruction printing.
This encompasses several changes which are all interconnected:
- Use the MC framework for printing almost all instructions.
- AsmStrings are now live.
- This introduces an indirection between LLVM vregs and WebAssembly registers,
and a new pass, WebAssemblyRegNumbering, for computing a basic the mapping.
This addresses some basic issues with argument registers and unused registers.
- The way ARGUMENT instructions are handled no longer generates redundant
get_local+set_local for every argument.
This also changes the assembly syntax somewhat; most notably, MC's printing
does not use sigils on label names, so those are no longer present, and
push/pop now have a sigil to keep them unambiguous.
The usage of set_local/get_local/$push/$pop will continue to evolve
significantly. This patch is just one step of a larger change.
llvm-svn: 252910
This encompasses several changes which are all interconnected:
- Use the MC framework for printing almost all instructions.
- AsmStrings are now live.
- This introduces an indirection between LLVM vregs and WebAssembly registers,
and a new pass, WebAssemblyRegNumbering, for computing a basic the mapping.
This addresses some basic issues with argument registers and unused registers.
- The way ARGUMENT instructions are handled no longer generates redundant
get_local+set_local for every argument.
This also changes the assembly syntax somewhat; most notably, MC's printing
use sigils on label names, so those are no longer present, and push/pop now
have a sigil to keep them unambiguous.
The usage of set_local/get_local/$push/$pop will continue to evolve
significantly. This patch is just one step of a larger change.
llvm-svn: 252858
Summary:
Follow the same syntax as for the spec repo. Both have evolved slightly
independently and need to converge again.
This, along with wasmate changes, allows me to do the following:
echo "int add(int a, int b) { return a + b; }" > add.c
./out/bin/clang -O2 -S --target=wasm32-unknown-unknown add.c -o add.wack
./experimental/prototype-wasmate/wasmate.py add.wack > add.wast
./sexpr-wasm-prototype/out/sexpr-wasm add.wast -o add.wasm
./sexpr-wasm-prototype/third_party/v8-native-prototype/v8/v8/out/Release/d8 -e "print(WASM.instantiateModule(readbuffer('add.wasm'), {print:print}).add(42, 1337));"
As you'd expect, the d8 shell prints out the right value.
Reviewers: sunfish
Subscribers: jfb, llvm-commits, dschuff
Differential Revision: http://reviews.llvm.org/D13712
llvm-svn: 250480
This new syntax is built around putting each instruction on its own line
in a "mnemonic op, op, op" like syntax. It also uses conventional data
section directives like ".byte" and so on rather than requiring everything
to be in hierarchical S-expression format. This is a more natural syntax
for a ".s" file format from the perspective of LLVM MC and related tools,
while remaining easy to translate into other forms as needed.
llvm-svn: 249364