Revert "compiler: enabled vectorize option"

This reverts commit 636898c302.

RELEASE_NOTES.rst

@@ -28,7 +28,6 @@ Highlights:
    - SERDES TTL inputs can now detect edges on pulses that are shorter
      than the RTIO period (https://github.com/m-labs/artiq/issues/1432)
    - Improved performance for kernel RPC involving list and array.
-   - Improved performance for computation involving loops.
 * Coredevice SI to mu conversions now always return valid codes, or raise a ``ValueError``.
 * Zotino now exposes  ``voltage_to_mu()``
 * ``ad9910``: The maximum amplitude scale factor is now ``0x3fff`` (was ``0x3ffe``

artiq/compiler/targets.py

@@ -105,11 +105,7 @@ class Target:
         return llmachine
 
     def optimize(self, llmodule):
-        pmb = llvm.create_pass_manager_builder()
-        pmb.slp_vectorize = True
-        pmb.loop_vectorize = True
         llpassmgr = llvm.create_module_pass_manager()
-        pmb.populate(llpassmgr)
 
         # Register our alias analysis passes.
         llpassmgr.add_basic_alias_analysis_pass()