tsan: fix XMM register corruption in hacky call
The compiler does not recognize HACKY_CALL as a call (we intentionally hide it from the compiler so that it can compile non-leaf functions as leaf functions). To compensate for that hacky call thunk saves and restores all caller-saved registers. However, it saves only general-purposes registers and does not save XMM registers. This is a latent bug that was masked up until a recent "NFC" commit d736002e ("tsan: move memory access functions to a separate file"), which allowed more inlining and exposed the 10-year bug. Save and restore caller-saved XMM registers (all) as well. Currently the bug manifests as e.g. frexp interceptor messes the return value and the added test fails with: i=8177 y=0.000000 exp=4 Reviewed By: melver Differential Revision: https://reviews.llvm.org/D113742
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