From 00ab4df39bfae90a8f3f197a637b5546265eb5a4 Mon Sep 17 00:00:00 2001
From: Charles Oliver Nutter <headius@headius.com>
Date: Tue, 28 Nov 2023 23:08:04 -0600
Subject: [PATCH] Implement integer math JIT for IR

---
 .../ir/instructions/IntegerMathInstr.java     |  6 ++++-
 .../java/org/jruby/ir/targets/JVMVisitor.java | 22 +++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/org/jruby/ir/instructions/IntegerMathInstr.java b/core/src/main/java/org/jruby/ir/instructions/IntegerMathInstr.java
index d80625a4e85e..a2be073aa255 100644
--- a/core/src/main/java/org/jruby/ir/instructions/IntegerMathInstr.java
+++ b/core/src/main/java/org/jruby/ir/instructions/IntegerMathInstr.java
@@ -74,7 +74,11 @@ public Object interpret(ThreadContext context, StaticScope currScope, DynamicSco
             case DIVIDE:
                 return value1 / value2;
             default:
-                throw new RuntimeException("BIntInstr has unknown op");
+                throw new RuntimeException("IntegerMathInstr has unknown op");
         }
     }
+
+    public Op getOp() {
+        return op;
+    }
 }
diff --git a/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java b/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java
index 4121a8233d12..9985a40bc49f 100644
--- a/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java
+++ b/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java
@@ -1749,6 +1749,28 @@ private void superCommon(String name, CallInstr instr, Operand[] args, Operand d
         jvmStoreLocal(instr.getResult());
     }
 
+    @Override
+    public void IntegerMathInstr(IntegerMathInstr instr) {
+        visit(instr.getOperand1());
+        visit(instr.getOperand2());
+        switch (instr.getOp()) {
+            case ADD:
+                jvmAdapter().iadd();
+                break;
+            case SUBTRACT:
+                jvmAdapter().isub();
+                break;
+            case MULTIPLY:
+                jvmAdapter().imul();
+                break;
+            case DIVIDE:
+                jvmAdapter().idiv();
+            default:
+                throw new NotCompilableException("IntegerMathInstr has unknown op: " + instr);
+        }
+        jvmStoreLocal(instr.getResult());
+    }
+
     @Override
     public void JumpInstr(JumpInstr jumpinstr) {
         jvmMethod().goTo(getJVMLabel(jumpinstr.getJumpTarget()));