From 6578cc4fb17647b8e5c72bf55de0ca059d834eec Mon Sep 17 00:00:00 2001
From: MITSUNARI Shigeo <herumi@nifty.com>
Date: Fri, 15 Sep 2023 11:12:06 +0900
Subject: [PATCH] not run

---
 sample/bf.cpp | 121 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 121 insertions(+)
 create mode 100644 sample/bf.cpp

diff --git a/sample/bf.cpp b/sample/bf.cpp
new file mode 100644
index 0000000..691a01e
--- /dev/null
+++ b/sample/bf.cpp
@@ -0,0 +1,121 @@
+#include <fstream>
+#include <stack>
+#include <stdio.h>
+#include <stdlib.h>
+#include <xbyak_riscv/xbyak_riscv.hpp>
+
+class Brainfuck : public Xbyak_riscv::CodeGenerator {
+public:
+	int getContinuousChar(std::istream &is, char c) {
+		int count = 1;
+		char p;
+		while (is >> p) {
+			if (p != c)
+				break;
+			count++;
+		}
+		is.unget();
+		return count;
+	}
+	Brainfuck(std::istream &is) : CodeGenerator(100000) {
+		// void (*)(void* putchar, void* getchar, int *stack)
+		using namespace Xbyak_riscv;
+		const auto &pPutchar = s2;
+		const auto &pGetchar = s3;
+		const auto &stack = s4;
+		const int saveSize = 16*3;
+		addi(sp, sp, -saveSize);
+		sd(pPutchar, sp, 16);
+		sd(pGetchar, sp, 24);
+		sd(stack, sp, 32);
+
+		mv(pPutchar, a0);
+		mv(pGetchar, a1);
+		mv(stack, a2);
+
+		std::stack<Label> labelF, labelB;
+		char c;
+		while (is >> c) {
+			switch (c) {
+			case '+':
+			case '-': {
+				int count = getContinuousChar(is, c);
+				ld(a0, stack);
+				// QQQ : not support large count
+				if (c == '+') {
+					addi(a0, a0, count);
+				} else {
+					addi(a0, a0, -count);
+				}
+				sd(a0, stack);
+			} break;
+			case '>':
+			case '<': {
+				int count = getContinuousChar(is, c) * 8;
+				if (c == '>') {
+					addi(stack, stack, count);
+				} else {
+					addi(stack, stack, -count);
+				}
+			} break;
+			case '.':
+				ld(a0, stack);
+				sd(ra, sp, 8);
+				jr(pPutchar);
+				ld(ra, sp, 8);
+				break;
+			case ',':
+				sd(ra, sp, 8);
+				jr(pGetchar);
+				ld(ra, sp, 8);
+				sd(a0, stack);
+				break;
+			case '[': {
+				Label B = L();
+				labelB.push(B);
+				ld(a0, stack);
+				Label F;
+				beq(a0, x0, F);
+				labelF.push(F);
+			} break;
+			case ']': {
+				Label B = labelB.top();
+				labelB.pop();
+				j_(B);
+				Label F = labelF.top();
+				labelF.pop();
+				L(F);
+			} break;
+			default:
+				break;
+			}
+		}
+
+		ld(stack, sp, 32);
+		ld(pGetchar, sp, 24);
+		ld(pPutchar, sp, 16);
+		addi(sp, sp, saveSize);
+		ret();
+	}
+};
+
+int main(int argc, char *argv[]) try {
+	if (argc != 2) {
+		fprintf(stderr, "bf filename.bf\n");
+		return 1;
+	}
+	std::ifstream ifs(argv[1]);
+	Brainfuck bf(ifs);
+	bf.ready();
+	static int64_t stack[128 * 1024];
+	auto f = bf.getCode<void (*)(const void *, const void *, int64_t *)>();
+#if 0
+	FILE *fp = fopen("bf.dump", "wb");
+	fwrite((const void*)f, bf.getSize(), 1, fp);
+	fclose(fp);
+#endif
+	f((const void *)putchar, (const void *)getchar, stack);
+} catch (std::exception &e) {
+	printf("ERR:%s\n", e.what());
+	return 1;
+}