[GlobalISel] Introduce a G_DYN_STACKALLOC opcode to represent dynamic allocas.

This just adds the opcode and verifier, it will be used to replace existing
dynamic alloca handling in a subsequent patch.

Differential Revision: https://reviews.llvm.org/D66677

llvm-svn: 369833

1 files changed, 21 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp
index c0c5a70fac8..727ce0af029 100644
--- a/llvm/lib/CodeGen/MachineVerifier.cpp
+++ b/llvm/lib/CodeGen/MachineVerifier.cpp
@@ -1437,6 +1437,27 @@ void MachineVerifier::verifyPreISelGenericInstruction(const MachineInstr *MI) {
 
     break;
   }
+  case TargetOpcode::G_DYN_STACKALLOC: {
+    const MachineOperand &DstOp = MI->getOperand(0);
+    const MachineOperand &AllocOp = MI->getOperand(1);
+    const MachineOperand &AlignOp = MI->getOperand(2);
+
+    if (!DstOp.isReg() || !MRI->getType(DstOp.getReg()).isPointer()) {
+      report("dst operand 0 must be a pointer type", MI);
+      break;
+    }
+
+    if (!AllocOp.isReg() || !MRI->getType(AllocOp.getReg()).isScalar()) {
+      report("src operand 1 must be a scalar reg type", MI);
+      break;
+    }
+
+    if (!AlignOp.isImm()) {
+      report("src operand 2 must be an immediate type", MI);
+      break;
+    }
+    break;
+  }
   default:
     break;
   }