зеркало из https://github.com/mozilla/gecko-dev.git
db99d20ce6
The wasm test machinery has functions `codegenTest{X64,X32,ARM64}_adhoc` to
compile tiny wasm fragments and compare generated code against expected
regexps. While useful these have the following limitations:
* arm(32) isn't handled
* results from the other 3 Tier-1 targets, given the same input, are
potentially scattered across multiple files
These make it difficult to systematically assess folding and codegen effects
across the 4 Tier-1 platforms.
The attached patch:
* adds `codegenTestMultiplatform_adhoc`, which takes expected-result strings
for all 4 platforms and uses the correct one. Debug printing is also
improved. For convenience, the result string for 32-bit arm may be omitted,
in which case the relevant test is not run.
* adds tests for the folding rules shown below, for both 32- and 64-bit
operations.
mips64 is not supported, because it has no disassembly facility.
Various missing folding rules and much regalloc badness is thereby exposed.
The behaviour of the compilers is unaltered; this patch merely serves as a
convenient way to assess and document the current folding behaviour.
```
0 * x => 0
1 * x => x
-1 * x => -x
2 * x => x + x
4 * x => x << 2
x * 0 => 0
x * 1 => x
x * -1 => -x
x * 2 => x + x
x * 4 => x << 2
x >> 0 => x (any shift kind: shl, shrU, shrS)
x + 0 => x
0 + x => x
x + x => x << 1
x - 0 => x
0 - x => -x
x - x => 0
```
Differential Revision: https://phabricator.services.mozilla.com/D138129
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| ductwork/debugger | ||
| examples | ||
| loader | ||
| public | ||
| src | ||
| xpconnect | ||
| app.mozbuild | ||
| ffi.configure | ||
| moz.build | ||
| moz.configure | ||
| sub.configure | ||