Revert "[csa] Fix semantics of PopAndReturn"
This reverts commit 5e5eaf79. Reason for revert: Failure on V8 Linux gcc https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20gcc/8929? 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,ishell@chromium.org Change-Id: I2673982a8f51cbecf421af11b0ce5ad5031fb406 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/+/2465656Reviewed-by: Zhi An Ng <zhin@chromium.org> Commit-Queue: Zhi An Ng <zhin@chromium.org> Cr-Commit-Position: refs/heads/master@{#70458}
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