[ARM] Add FeatureHasNoBranchPredictor for Thumb1 cores

Mark v6m/v8m-baseline cores as having no branch predictors. This should
not alter very much on its own, but is more correct as the cores do not
have branch predictors and can help in the future.

diff --git a/llvm/lib/Target/ARM/ARM.td b/llvm/lib/Target/ARM/ARM.td
index 7fe10c7..9da2bdb 100644 (file)
--- a/llvm/lib/Target/ARM/ARM.td
+++ b/llvm/lib/Target/ARM/ARM.td
@@ -1000,10 +1000,14 @@ def : Processor<"arm1136jf-s",      ARMV6Itineraries,   [ARMv6,
                                                          FeatureVFP2,
                                                          FeatureHasSlowFPVMLx]>;
 
-def : Processor<"cortex-m0",        ARMV6Itineraries,   [ARMv6m]>;
-def : Processor<"cortex-m0plus",    ARMV6Itineraries,   [ARMv6m]>;
-def : Processor<"cortex-m1",        ARMV6Itineraries,   [ARMv6m]>;
-def : Processor<"sc000",            ARMV6Itineraries,   [ARMv6m]>;
+def : Processor<"cortex-m0",        ARMV6Itineraries,   [ARMv6m,
+                                                         FeatureHasNoBranchPredictor]>;
+def : Processor<"cortex-m0plus",    ARMV6Itineraries,   [ARMv6m,
+                                                         FeatureHasNoBranchPredictor]>;
+def : Processor<"cortex-m1",        ARMV6Itineraries,   [ARMv6m,
+                                                         FeatureHasNoBranchPredictor]>;
+def : Processor<"sc000",            ARMV6Itineraries,   [ARMv6m,
+                                                         FeatureHasNoBranchPredictor]>;
 
 def : Processor<"arm1176j-s",       ARMV6Itineraries,   [ARMv6kz]>;
 def : Processor<"arm1176jz-s",      ARMV6Itineraries,   [ARMv6kz]>;
@@ -1199,7 +1203,8 @@ def : ProcessorModel<"cortex-m7", CortexM7Model,        [ARMv7em,
                                                          FeatureUseMISched]>;
 
 def : ProcNoItin<"cortex-m23",                          [ARMv8mBaseline,
-                                                         FeatureNoMovt]>;
+                                                         FeatureNoMovt,
+                                                         FeatureHasNoBranchPredictor]>;
 
 def : ProcessorModel<"cortex-m33", CortexM4Model,       [ARMv8mMainline,
                                                          FeatureDSP,