AMDGPU: Diagnose illegal SGPR to VGPR copies

This is possible in ways that are not compiler bugs,
so stop asserting on them.

This emits an extra error when emitting objects when it
can't encode the new pseudo, but I'm not sure that matters.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299712 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 40 insertions, 3 deletions

diff --git a/lib/Target/AMDGPU/SIInstrInfo.cpp b/lib/Target/AMDGPU/SIInstrInfo.cpp
index fd01a09b751..b1e4c9a7aaa 100644
--- a/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ b/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -21,6 +21,7 @@
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/ScheduleDAG.h"
+#include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/IR/Function.h"
 #include "llvm/CodeGen/RegisterScavenging.h"
 #include "llvm/MC/MCInstrDesc.h"
@@ -347,6 +348,21 @@ bool SIInstrInfo::shouldClusterMemOps(MachineInstr &FirstLdSt,
   return (NumLoads * DstRC->getSize()) <= LoadClusterThreshold;
 }
 
+static void reportIllegalCopy(const SIInstrInfo *TII, MachineBasicBlock &MBB,
+                              MachineBasicBlock::iterator MI,
+                              const DebugLoc &DL, unsigned DestReg,
+                              unsigned SrcReg, bool KillSrc) {
+  MachineFunction *MF = MBB.getParent();
+  DiagnosticInfoUnsupported IllegalCopy(*MF->getFunction(),
+                                        "illegal SGPR to VGPR copy",
+                                        DL, DS_Error);
+  LLVMContext &C = MF->getFunction()->getContext();
+  C.diagnose(IllegalCopy);
+
+  BuildMI(MBB, MI, DL, TII->get(AMDGPU::SI_ILLEGAL_COPY), DestReg)
+    .addReg(SrcReg, getKillRegState(KillSrc));
+}
+
 void SIInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
                               MachineBasicBlock::iterator MI,
                               const DebugLoc &DL, unsigned DestReg,
@@ -370,7 +386,11 @@ void SIInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
       return;
     }
 
-    assert(AMDGPU::SReg_32RegClass.contains(SrcReg));
+    if (!AMDGPU::SReg_32RegClass.contains(SrcReg)) {
+      reportIllegalCopy(this, MBB, MI, DL, DestReg, SrcReg, KillSrc);
+      return;
+    }
+
     BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B32), DestReg)
             .addReg(SrcReg, getKillRegState(KillSrc));
     return;
@@ -392,7 +412,11 @@ void SIInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
       return;
     }
 
-    assert(AMDGPU::SReg_64RegClass.contains(SrcReg));
+    if (!AMDGPU::SReg_64RegClass.contains(SrcReg)) {
+      reportIllegalCopy(this, MBB, MI, DL, DestReg, SrcReg, KillSrc);
+      return;
+    }
+
     BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B64), DestReg)
             .addReg(SrcReg, getKillRegState(KillSrc));
     return;
@@ -416,8 +440,14 @@ void SIInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
       Opcode = AMDGPU::S_MOV_B32;
       EltSize = 4;
     }
+
+    if (!RI.isSGPRClass(RI.getPhysRegClass(SrcReg))) {
+      reportIllegalCopy(this, MBB, MI, DL, DestReg, SrcReg, KillSrc);
+      return;
+    }
   }
 
+
   ArrayRef<int16_t> SubIndices = RI.getRegSplitParts(RC, EltSize);
   bool Forward = RI.getHWRegIndex(DestReg) <= RI.getHWRegIndex(SrcReg);
 
@@ -3223,12 +3253,15 @@ void SIInstrInfo::moveToVALU(MachineInstr &TopInst) const {
     bool HasDst = Inst.getOperand(0).isReg() && Inst.getOperand(0).isDef();
     unsigned NewDstReg = AMDGPU::NoRegister;
     if (HasDst) {
+      unsigned DstReg = Inst.getOperand(0).getReg();
+      if (TargetRegisterInfo::isPhysicalRegister(DstReg))
+        continue;
+
       // Update the destination register class.
       const TargetRegisterClass *NewDstRC = getDestEquivalentVGPRClass(Inst);
       if (!NewDstRC)
         continue;
 
-      unsigned DstReg = Inst.getOperand(0).getReg();
       if (Inst.isCopy() &&
           TargetRegisterInfo::isVirtualRegister(Inst.getOperand(1).getReg()) &&
           NewDstRC == RI.getRegClassForReg(MRI, Inst.getOperand(1).getReg())) {
diff --git a/lib/Target/AMDGPU/SIInstructions.td b/lib/Target/AMDGPU/SIInstructions.td
index fde14792ea6..2f89503e129 100644
--- a/lib/Target/AMDGPU/SIInstructions.td
+++ b/lib/Target/AMDGPU/SIInstructions.td
@@ -248,6 +248,10 @@ def SI_KILL_TERMINATOR : SPseudoInstSI <
   let isTerminator = 1;
 }
 
+def SI_ILLEGAL_COPY : SPseudoInstSI <
+  (outs unknown:$dst), (ins unknown:$src),
+  [], " ; illegal copy $src to $dst">;
+
 } // End Uses = [EXEC], Defs = [EXEC,VCC]
 
 // Branch on undef scc. Used to avoid intermediate copy from