1 files changed, 94 insertions, 0 deletions
diff --git a/src/ir_print.cpp b/src/ir_print.cpp
new file mode 100644
index 0000000000..e3033f2db7
--- /dev/null
+++ b/src/ir_print.cpp
@@ -0,0 +1,94 @@
+#include "ir_print.hpp"
+
+struct IrPrint {
+    FILE *f;
+    int indent;
+    int indent_size;
+};
+
+static void ir_print_indent(IrPrint *irp) {
+    for (int i = 0; i < irp->indent; i += 1) {
+        fprintf(irp->f, " ");
+    }
+}
+
+static void ir_print_prefix(IrPrint *irp, IrInstruction *instruction) {
+    ir_print_indent(irp);
+    fprintf(irp->f, "#%-3zu| ", instruction->debug_id);
+}
+
+static void ir_print_return(IrPrint *irp, IrInstructionReturn *return_instruction) {
+    ir_print_prefix(irp, &return_instruction->base);
+    assert(return_instruction->value);
+    fprintf(irp->f, "return #%zu;\n", return_instruction->value->debug_id);
+}
+
+static void ir_print_const(IrPrint *irp, IrInstructionConst *const_instruction) {
+    ir_print_prefix(irp, &const_instruction->base);
+    switch (const_instruction->base.type_entry->id) {
+        case TypeTableEntryIdInvalid:
+            zig_unreachable();
+        case TypeTableEntryIdVoid:
+            fprintf(irp->f, "void\n");
+            break;
+        case TypeTableEntryIdVar:
+        case TypeTableEntryIdMetaType:
+        case TypeTableEntryIdBool:
+        case TypeTableEntryIdUnreachable:
+        case TypeTableEntryIdInt:
+        case TypeTableEntryIdFloat:
+        case TypeTableEntryIdPointer:
+        case TypeTableEntryIdArray:
+        case TypeTableEntryIdStruct:
+        case TypeTableEntryIdNumLitFloat:
+        case TypeTableEntryIdNumLitInt:
+        case TypeTableEntryIdUndefLit:
+        case TypeTableEntryIdNullLit:
+        case TypeTableEntryIdMaybe:
+        case TypeTableEntryIdErrorUnion:
+        case TypeTableEntryIdPureError:
+        case TypeTableEntryIdEnum:
+        case TypeTableEntryIdUnion:
+        case TypeTableEntryIdFn:
+        case TypeTableEntryIdTypeDecl:
+        case TypeTableEntryIdNamespace:
+        case TypeTableEntryIdBlock:
+        case TypeTableEntryIdGenericFn:
+            zig_panic("TODO render more constant types in IR printer");
+    }
+}
+
+void ir_print(FILE *f, IrExecutable *executable, int indent_size) {
+    IrPrint ir_print = {};
+    IrPrint *irp = &ir_print;
+    irp->f = f;
+    irp->indent = indent_size;
+    irp->indent_size = indent_size;
+
+    for (size_t i = 0; i < executable->basic_block_count; i += 1) {
+        IrBasicBlock *current_block = executable->basic_block_list[i];
+        for (IrInstruction *instruction = current_block->first; instruction != nullptr;
+                instruction = instruction->next)
+        {
+            switch (instruction->id) {
+                case IrInstructionIdInvalid:
+                    zig_unreachable();
+                case IrInstructionIdReturn:
+                    ir_print_return(irp, (IrInstructionReturn *)instruction);
+                    break;
+                case IrInstructionIdConst:
+                    ir_print_const(irp, (IrInstructionConst *)instruction);
+                    break;
+                case IrInstructionIdCondBr:
+                case IrInstructionIdSwitchBr:
+                case IrInstructionIdPhi:
+                case IrInstructionIdBinOp:
+                case IrInstructionIdLoadVar:
+                case IrInstructionIdStoreVar:
+                case IrInstructionIdCall:
+                case IrInstructionIdBuiltinCall:
+                    zig_panic("TODO print more IR instructions");
+            }
+        }
+    }
+}