[PATCH] [asan] Disable stack malloc on functions containing inline assembly

Alexander Potapenko glider at google.com
Fri Jun 26 05:09:55 PDT 2015

In http://reviews.llvm.org/D10719#194702, @zaks.anna wrote:

> Alex, I don't fully understand why we think this could be a problem with register allocator. Could you explain this in more detail?

Well, IIUC the piece of assembly code you've provided requires only 5 general-purpose registers, while x86_64 has 16 of them. With register spilling it should be possible to run using a single register for the rest of the function (which isn't really optimal). Given we have more than one register left, I consider the regallocator to be a bit too lazy in this case (not to downplay its value in many other cases).



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