cpu: Added interface for vector reg file

This patch adds some more functionality to the cpu model and the arch to
interface with the vector register file.

This change consists mainly of augmenting ThreadContexts and ExecContexts
with calls to get/set full vectors, underlying microarchitectural elements
or lanes. Those are meant to interface with the vector register file. All
classes that implement this interface also get an appropriate implementation.

This requires implementing the vector register file for the different
models using the VecRegContainer class.

This change set also updates the Result abstraction to contemplate the
possibility of having a vector as result.

The changes also affect how the remote_gdb connection works.

There are some (nasty) side effects, such as the need to define dummy
numPhysVecRegs parameter values for architectures that do not implement
vector extensions.

Nathanael Premillieu's work with an increasing number of fixes and
improvements of mine.

Change-Id: Iee65f4e8b03abfe1e94e6940a51b68d0977fd5bb
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
[ Fix RISCV build issues and CC reg free list initialisation ]
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2705

4 files changed, 147 insertions, 5 deletions

diff --git a/src/cpu/minor/dyn_inst.cc b/src/cpu/minor/dyn_inst.cc
index 1ed598833..756b214bd 100644
--- a/src/cpu/minor/dyn_inst.cc
+++ b/src/cpu/minor/dyn_inst.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014 ARM Limited
+ * Copyright (c) 2013-2014, 2016 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -153,6 +153,13 @@ printRegName(std::ostream &os, const RegId& reg)
       case FloatRegClass:
         os << 'f' << static_cast<unsigned int>(reg.index());
         break;
+      case VecRegClass:
+        os << 'v' << static_cast<unsigned int>(reg.index());
+        break;
+      case VecElemClass:
+        os << 'v' << static_cast<unsigned int>(reg.index()) << '[' <<
+              static_cast<unsigned int>(reg.elemIndex()) << ']';
+        break;
       case IntRegClass:
         if (reg.isZeroReg()) {
             os << 'z';
@@ -162,6 +169,8 @@ printRegName(std::ostream &os, const RegId& reg)
         break;
       case CCRegClass:
         os << 'c' << static_cast<unsigned int>(reg.index());
+      default:
+        panic("Unknown register class: %d", (int)reg.classValue());
     }
 }
 
diff --git a/src/cpu/minor/exec_context.hh b/src/cpu/minor/exec_context.hh
index e91b7a6dd..4b3a02fca 100644
--- a/src/cpu/minor/exec_context.hh
+++ b/src/cpu/minor/exec_context.hh
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2014 ARM Limited
+ * Copyright (c) 2011-2014, 2016 ARM Limited
  * Copyright (c) 2013 Advanced Micro Devices, Inc.
  * All rights reserved
  *
@@ -145,6 +145,30 @@ class ExecContext : public ::ExecContext
         return thread.readFloatRegBits(reg.index());
     }
 
+    const TheISA::VecRegContainer&
+    readVecRegOperand(const StaticInst *si, int idx) const override
+    {
+        const RegId& reg = si->srcRegIdx(idx);
+        assert(reg.isVecReg());
+        return thread.readVecReg(reg);
+    }
+
+    TheISA::VecRegContainer&
+    getWritableVecRegOperand(const StaticInst *si, int idx) override
+    {
+        const RegId& reg = si->destRegIdx(idx);
+        assert(reg.isVecReg());
+        return thread.getWritableVecReg(reg);
+    }
+
+    TheISA::VecElem
+    readVecElemOperand(const StaticInst *si, int idx) const override
+    {
+        const RegId& reg = si->srcRegIdx(idx);
+        assert(reg.isVecReg());
+        return thread.readVecElem(reg);
+    }
+
     void
     setIntRegOperand(const StaticInst *si, int idx, IntReg val) override
     {
@@ -171,6 +195,102 @@ class ExecContext : public ::ExecContext
         thread.setFloatRegBits(reg.index(), val);
     }
 
+    void
+    setVecRegOperand(const StaticInst *si, int idx,
+                     const TheISA::VecRegContainer& val) override
+    {
+        const RegId& reg = si->destRegIdx(idx);
+        assert(reg.isVecReg());
+        thread.setVecReg(reg, val);
+    }
+
+    /** Vector Register Lane Interfaces. */
+    /** @{ */
+    /** Reads source vector 8bit operand. */
+    ConstVecLane8
+    readVec8BitLaneOperand(const StaticInst *si, int idx) const
+                            override
+    {
+        const RegId& reg = si->srcRegIdx(idx);
+        assert(reg.isVecReg());
+        return thread.readVec8BitLaneReg(reg);
+    }
+
+    /** Reads source vector 16bit operand. */
+    ConstVecLane16
+    readVec16BitLaneOperand(const StaticInst *si, int idx) const
+                            override
+    {
+        const RegId& reg = si->srcRegIdx(idx);
+        assert(reg.isVecReg());
+        return thread.readVec16BitLaneReg(reg);
+    }
+
+    /** Reads source vector 32bit operand. */
+    ConstVecLane32
+    readVec32BitLaneOperand(const StaticInst *si, int idx) const
+                            override
+    {
+        const RegId& reg = si->srcRegIdx(idx);
+        assert(reg.isVecReg());
+        return thread.readVec32BitLaneReg(reg);
+    }
+
+    /** Reads source vector 64bit operand. */
+    ConstVecLane64
+    readVec64BitLaneOperand(const StaticInst *si, int idx) const
+                            override
+    {
+        const RegId& reg = si->srcRegIdx(idx);
+        assert(reg.isVecReg());
+        return thread.readVec64BitLaneReg(reg);
+    }
+
+    /** Write a lane of the destination vector operand. */
+    template <typename LD>
+    void
+    setVecLaneOperandT(const StaticInst *si, int idx,
+            const LD& val)
+    {
+        const RegId& reg = si->destRegIdx(idx);
+        assert(reg.isVecReg());
+        return thread.setVecLane(reg, val);
+    }
+    virtual void
+    setVecLaneOperand(const StaticInst *si, int idx,
+            const LaneData<LaneSize::Byte>& val) override
+    {
+        setVecLaneOperandT(si, idx, val);
+    }
+    virtual void
+    setVecLaneOperand(const StaticInst *si, int idx,
+            const LaneData<LaneSize::TwoByte>& val) override
+    {
+        setVecLaneOperandT(si, idx, val);
+    }
+    virtual void
+    setVecLaneOperand(const StaticInst *si, int idx,
+            const LaneData<LaneSize::FourByte>& val) override
+    {
+        setVecLaneOperandT(si, idx, val);
+    }
+    virtual void
+    setVecLaneOperand(const StaticInst *si, int idx,
+            const LaneData<LaneSize::EightByte>& val) override
+    {
+        setVecLaneOperandT(si, idx, val);
+    }
+    /** @} */
+
+    void
+    setVecElemOperand(const StaticInst *si, int idx,
+                      const TheISA::VecElem val) override
+    {
+        const RegId& reg = si->destRegIdx(idx);
+        assert(reg.isVecReg());
+        thread.setVecElem(reg, val);
+    }
+
     bool
     readPredicate() override
     {
diff --git a/src/cpu/minor/scoreboard.cc b/src/cpu/minor/scoreboard.cc
index e3497a5cf..c56d3b303 100644
--- a/src/cpu/minor/scoreboard.cc
+++ b/src/cpu/minor/scoreboard.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014 ARM Limited
+ * Copyright (c) 2013-2014, 2016 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -67,6 +67,16 @@ Scoreboard::findIndex(const RegId& reg, Index &scoreboard_index)
                 reg.index();
             ret = true;
             break;
+          case VecRegClass:
+            scoreboard_index = TheISA::NumIntRegs + TheISA::NumCCRegs +
+                TheISA::NumFloatRegs + reg.index();
+            ret = true;
+            break;
+          case VecElemClass:
+            scoreboard_index = TheISA::NumIntRegs + TheISA::NumCCRegs +
+                TheISA::NumFloatRegs + TheISA::NumVecRegs + reg.index();
+            ret = true;
+            break;
           case CCRegClass:
             scoreboard_index = TheISA::NumIntRegs + reg.index();
             ret = true;
@@ -75,6 +85,9 @@ Scoreboard::findIndex(const RegId& reg, Index &scoreboard_index)
               /* Don't bother with Misc registers */
             ret = false;
             break;
+          default:
+            panic("Unknown register class: %d",
+                    static_cast<int>(reg.classValue()));
         }
     }
 
diff --git a/src/cpu/minor/scoreboard.hh b/src/cpu/minor/scoreboard.hh
index 7fe5002f9..9e42c2a6b 100644
--- a/src/cpu/minor/scoreboard.hh
+++ b/src/cpu/minor/scoreboard.hh
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014 ARM Limited
+ * Copyright (c) 2013-2014, 2016 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -94,7 +94,7 @@ class Scoreboard : public Named
     Scoreboard(const std::string &name) :
         Named(name),
         numRegs(TheISA::NumIntRegs + TheISA::NumCCRegs +
-            TheISA::NumFloatRegs),
+            TheISA::NumFloatRegs + TheISA::NumVecRegs),
         numResults(numRegs, 0),
         numUnpredictableResults(numRegs, 0),
         fuIndices(numRegs, 0),