Peter Maydell 3ae5543825 target/arm: Implement v8.1M low-overhead-loop instructions ... v8.1M's "low-overhead-loop" extension has three instructions for looping: * DLS (start of a do-loop) * WLS (start of a while-loop) * LE (end of a loop) The loop-start instructions are both simple operations to start a loop whose iteration count (if any) is in LR. The loop-end instruction handles "decrement iteration count and jump back to loop start"; it also caches the information about the branch back to the start of the loop to improve performance of the branch on subsequent iterations. As with the branch-future instructions, the architecture permits an implementation to discard the LO_BRANCH_INFO cache at any time, and QEMU takes the IMPDEF option to never set it in the first place (equivalent to discarding it immediately), because for us a "real" implementation would be unnecessary complexity. (This implementation only provides the simple looping constructs; the vector extension MVE (Helium) adds some extra variants to handle looping across vectors. We'll add those later when we implement MVE.) Backports commit b7226369721896ab9ef71544e4fe95b40710e05a		2021-03-01 20:29:04 -05:00
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arm	target/arm: Implement v8.1M low-overhead-loop instructions	2021-03-01 20:29:04 -05:00
i386	i386/cpu: Clear FEAT_XSAVE_COMP_{LO,HI} when XSAVE is not available	2021-03-01 19:04:03 -05:00
m68k	target/m68k: consolidate physical translation offset into get_physical_address()	2021-02-25 23:13:48 -05:00
mips	target/mips: Support variable page size	2020-06-14 21:09:51 -04:00
riscv	target/riscv: Set instance_align on RISCVCPU TypeInfo	2021-03-01 19:00:27 -05:00
sparc	softfloat: Name compare relation enum	2020-05-21 18:08:52 -04:00