93315e46b0
Add a new "spec" bitfield to branch entries for providing speculation information. This will be populated using hints provided by branch sampling features on supported hardware. The following cases are covered: * No branch speculation information is available * Branch is speculative but taken on the wrong path * Branch is non-speculative but taken on the correct path * Branch is speculative and taken on the correct path Suggested-by: Stephane Eranian <eranian@google.com> Signed-off-by: Sandipan Das <sandipan.das@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/834088c302faf21c7b665031dd111f424e509a64.1660211399.git.sandipan.das@amd.com