commit f9b549fbf572ac1b8b40ee86411eb9331a2bf458
author Hoa Nguyen <hoanguyen@ucdavis.edu> Fri Jul 12 12:09:30 2019 -0700
committer Hoa Nguyen <hoanguyen@ucdavis.edu> Tue Jul 16 20:26:31 2019 +0000
tree 95338742d3941dac89754102e7c619e95bf7996d
parent 93fadbcabef27580bcfd2647d1f66f5f5c31b7d3

arch-x86: add unconditional tag to calls/returns

The branch predictor checks whether an instruction is unconditional
branch before adding it or checking the RAS. With this change, the
RAS is significantly more effective for short running x86 workloads.

Change-Id: I60af5f2f583b898ad77f79f4b0478d6cda88fc21
Signed-off-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19448
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Gabe Black <gabeblack@google.com>

src/arch/x86/isa/macroop.isa

diff --git a/src/arch/x86/isa/macroop.isa b/src/arch/x86/isa/macroop.isa
index 7d72961..99d76b4 100644
--- a/src/arch/x86/isa/macroop.isa
+++ b/src/arch/x86/isa/macroop.isa
@@ -226,8 +226,10 @@
 
                     if self.function_call:
                         flags.append("IsCall")
+                        flags.append("IsUncondControl")
                     if self.function_return:
                         flags.append("IsReturn")
+                        flags.append("IsUncondControl")
                 else:
                     flags.append("IsDelayedCommit")