-
Ng Zhi An authored
In Liftoff, we were missing kS128 cases to load to/from stack. For the x64 and ARM64 instruction selector, the calculation of reverse_slot is incorrect for 128-bit values: - reverse_slot += 2 (size of 128-bit values, 2 pointers) - this copies from slot -2 into register - but the value starts at slot -1, it occupies slots -1 and -2 - we end up copying slot -2 (most significant half) of the register, and also slot -3, which is where rsi was store (Wasm instance addr) - the test ends up with a different result every time The calculation of reverse_slot is changed to follow how ia32 and ARM does it, which is to start with - reverse_slot = 0 - in the code-generator, add 1 to the slot - then after emitting Peek operation, reverse_slot += 2 The fixes for x64 and ARM64 are in both instruction-selector and code-generator. ia32 and ARM didn't support writing kSimd128 values yet, it was only a missing check in code-generator, so add that in. For ARM, the codegen is more involved, vld1 does not support addressing with an offset, so we have to do the addition into a scratch register. Also adding a test for returning multiple v128. V128 is not exposed to JavaScript, so we use a Wasm function call, and then an involved chain of extract lanes, returning 6 i32 which we verify the values of. It extracts the first and last lane of the i32x4 value in order to catch bugs where we write or read to a wrong stack slot (off by 1). The simd-scalar-lowering for kCall was only handling single s128 return, we adopt the way i64-lowering handles kCall, so that is can now handle any kinds of calls with s128 in the descriptor. Bug: v8:10794 Bug: chromium:1115230 Change-Id: I2ccdd55f6292bc5794be78053b27e14da8cce70e Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2355189 Commit-Queue: Zhi An Ng <zhin@chromium.org> Reviewed-by: Andreas Haas <ahaas@chromium.org> Reviewed-by: Bill Budge <bbudge@chromium.org> Cr-Commit-Position: refs/heads/master@{#69439}
360c9294