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AArch32/Armv8A introduced the performance deprecation of certain patterns of IT instructions. After some debate internal to ARM, this is now being reverted; i.e. no IT instruction patterns are performance deprecated anymore, as the perfomance degredation is not significant enough. This reverts the following: "ARMv8-A deprecates some uses of the T32 IT instruction. All uses of IT that apply to instructions other than a single subsequent 16-bit instruction from a restricted set are deprecated, as are explicit references to the PC within that single 16-bit instruction. This permits the non-deprecated forms of IT and subsequent instructions to be treated as a single 32-bit conditional instruction." The deprecation no longer applies, but the behaviour may be controlled by the -arm-restrict-it and -arm-no-restrict-it command-line options, with the latter being the default. No warnings about complex IT blocks will be generated. Reviewed By: dmgreen Differential Revision: https://reviews.llvm.org/D118044