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/+/2465839Reviewed-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}
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test/cctest/cctest-utils.h
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