arch,cpu: Add vector predicate registers

Latest-gen. vector/SIMD extensions, including the Arm Scalable Vector
Extension (SVE), introduce the notion of a predicate register file.
This changeset adds this feature across architectures and CPU models.

Change-Id: Iebcadbad89c0a582ff8b1b70de353305db603946
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13715
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/src/cpu/base_dyn_inst.hh b/src/cpu/base_dyn_inst.hh
index d81b58bdf..b87fd8b4e 100644
--- a/src/cpu/base_dyn_inst.hh
+++ b/src/cpu/base_dyn_inst.hh
@@ -584,6 +584,11 @@ class BaseDynInst : public ExecContext, public RefCounted
     {
         return staticInst->numVecElemDestRegs();
     }
+    int8_t
+    numVecPredDestRegs() const
+    {
+        return staticInst->numVecPredDestRegs();
+    }
 
     /** Returns the logical register index of the i'th destination register. */
     const RegId& destRegIdx(int i) const { return staticInst->destRegIdx(i); }
@@ -638,6 +643,16 @@ class BaseDynInst : public ExecContext, public RefCounted
                         InstResult::ResultType::VecElem));
         }
     }
+
+    /** Predicate result. */
+    template<typename T>
+    void setVecPredResult(T&& t)
+    {
+        if (instFlags[RecordResult]) {
+            instResult.push(InstResult(std::forward<T>(t),
+                            InstResult::ResultType::VecPredReg));
+        }
+    }
     /** @} */
 
     /** Records an integer register being set to a value. */
@@ -672,6 +687,13 @@ class BaseDynInst : public ExecContext, public RefCounted
         setVecElemResult(val);
     }
 
+    /** Record a vector register being set to a value */
+    void setVecPredRegOperand(const StaticInst *si, int idx,
+                              const VecPredRegContainer& val)
+    {
+        setVecPredResult(val);
+    }
+
     /** Records that one of the source registers is ready. */
     void markSrcRegReady();