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// |jit-test| --wasm-compiler=optimizing; --disable-wasm-huge-memory; --spectre-mitigations=off; skip-if: !hasDisassembler() || wasmCompileMode() != "ion" || !getBuildConfiguration("x64") || getBuildConfiguration("simulator") || getJitCompilerOptions()["ion.check-range-analysis"]; include:codegen-x64-test.js
// Spectre mitigation is disabled above to make the generated code simpler to
// match; ion.check-range-analysis makes a hash of the code and makes testing
// pointless.
// White-box testing of bounds check elimination on 64-bit systems.
//
// This is probably fairly brittle, but BCE on 64-bit platforms regressed (bug
// 1735207) without us noticing, so it's not like we can do without these tests.
//
// See also bce-x86-ion-codegen.js.
//
// If this turns out to be too brittle to be practical then an alternative to
// testing the output code is to do what we do for SIMD, record (in a log or
// buffer of some kind) that certain optimizations triggered, and then check the
// log.
var memTypes = [''];
if (wasmMemory64Enabled()) {
memTypes.push('i64')
}
for ( let memType of memTypes ) {
let dataType = memType ? memType : 'i32';
// Make sure the check for the second load is removed: the two load
// instructions should appear back-to-back in the output.
codegenTestX64_adhoc(
`(module
(memory ${memType} 1)
(func (export "f") (param ${dataType}) (result i32)
(local ${dataType})
(local.set 1 (${dataType}.add (local.get 0) (${dataType}.const 8)))
(i32.load (local.get 1))
drop
(i32.load (local.get 1))))`,
'f', `
48 3b .. cmp %r.., %r..
0f 83 .. 00 00 00 jnb 0x00000000000000..
41 8b .. .. movl \\(%r15,%r..,1\\), %e..
41 8b .. .. movl \\(%r15,%r..,1\\), %eax`,
{no_prefix:true});
// Make sure constant indices below the heap minimum do not require a bounds
// check.
codegenTestX64_adhoc(
`(module
(memory ${memType} 1)
(func (export "f") (result i32)
(i32.load (${dataType}.const 16))))`,
'f',
`41 8b 47 10 movl 0x10\\(%r15\\), %eax`);
// Ditto, even at the very limit of the known heap, extending into the guard
// page. This is an OOB access, of course, but it needs no explicit bounds
// check.
codegenTestX64_adhoc(
`(module
(memory ${memType} 1)
(func (export "f") (result i32)
(i32.load (${dataType}.const 65535))))`,
'f',
`
b8 ff ff 00 00 mov \\$0xFFFF, %eax
41 8b 04 07 movl \\(%r15,%rax,1\\), %eax`);
}