In the asm.js code translated to wasm, we call imported functions via a
WASM_TO_JS stub, which first calls the function and then calls ToNumber
on the return value. Exceptions can happen in both calls.
We were only ever reporting the location of the function call, whereas
asm.js code executed via turbofan reported the location of the type
coercion operator ("+" on "+foo()" or "|" on "foo()|0").
This CL implements the same behaviour for asm.js code translated to
wasm. The following is changed:
- the AsmWasmBuilder records the parent node when descending on a binary
operator (also "+foo()" is represented by a binary operation).
- it stores not one location per call in the source position side
table, but two (one for the call, one for the parent which does the
type coercion).
- the wasm compiler annotates the source positions "0" and "1" to the
two calls in the WASM_TO_JS wrapper (only if the module origin is
asm.js).
- during stack trace generation (in the StackTraceIterator), when we
move from the WASM_TO_JS frame to the WASM frame, we remember at which
call inside the WASM_TO_JS wrapper we are, and encode this information
in the generated caller state, used for the WASM frame.
- the same information is also stored in the FrameArray which is used
to reconstruct the stack trace later.
R=titzer@chromium.org, bradnelson@chromium.orgCC=jgruber@chromium.org
BUG=v8:4203,v8:5724
Review-Url: https://codereview.chromium.org/2555243002
Cr-Commit-Position: refs/heads/master@{#41599}
94cd46b55e