Revert "Reland "[csa] Fix semantics of PopAndReturn""
This reverts commit 3593ee83. Reason for revert: MSan issues: https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20MSAN/34798 Original change's description: > Reland "[csa] Fix semantics of PopAndReturn" > > This is a reland of 5e5eaf79 > > This CL fixes the "function returns address of local variable" issue > which GCC was complaining about by using inline assembly instead of > address of a local for getting stack pointer approximation. > > Original change's description: > > [csa] Fix semantics of PopAndReturn > > > > This CL prohibits using PopAndReturn from the builtins that > > have calling convention with arguments on the stack. > > > > This CL also updates the PopAndReturn tests so that even off-by-one > > errors in the number of poped arguments are caught which was not the > > case before. > > > > Motivation: > > > > PopAndReturn is supposed to be using ONLY in CSA/Torque builtins for > > dropping ALL JS arguments that are currently located on the stack. > > Disallowing PopAndReturn in builtins with stack arguments simplifies > > semantics of this instruction because in case of presence of declared > > stack parameters it's impossible to distinguish the following cases: > > 1) stack parameter is included in JS arguments (and therefore it will > > be dropped as a part of 'pop' number of arguments), > > 2) stack parameter is NOT included in JS arguments (and therefore it > > should be dropped in ADDITION to the 'pop' number of arguments). > > > > This issue wasn't noticed before because builtins with stack parameters > > relied on adapter frames machinery to ensure that the expected > > parameters are present on the stack, but on the same time the adapter > > frame tearing down code was effectively recovering the stack pointer > > potentially broken by the CSA builtin. > > > > Once we get rid of the arguments adapter frames keeping stack pointer > > in a valid state becomes crucial. > > > > Bug: v8:5269, v8:10201 > > Change-Id: Id3ea9730bb0d41d17999c73136c4dfada374a822 > > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2460819 > > Commit-Queue: Igor Sheludko <ishell@chromium.org> > > Reviewed-by: Tobias Tebbi <tebbi@chromium.org> > > Cr-Commit-Position: refs/heads/master@{#70454} > > Tbr: tebbi@chromium.org > Bug: v8:5269 > Bug: v8:10201 > Change-Id: Ic1a05fcc4efd2068538bff28189545cfd2617d9b > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2465839 > Reviewed-by: Igor Sheludko <ishell@chromium.org> > Reviewed-by: Victor Gomes <victorgomes@chromium.org> > Commit-Queue: Igor Sheludko <ishell@chromium.org> > Cr-Commit-Position: refs/heads/master@{#70483} TBR=tebbi@chromium.org,ishell@chromium.org,victorgomes@chromium.org Change-Id: Icbd71d744a519a58e49feb917109228631b9d9a3 No-Presubmit: true No-Tree-Checks: true No-Try: true Bug: v8:5269 Bug: v8:10201 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2467846Reviewed-by: Clemens Backes <clemensb@chromium.org> Commit-Queue: Clemens Backes <clemensb@chromium.org> Cr-Commit-Position: refs/heads/master@{#70485}
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