sea-of-blocks.cpp

#include <iostream>
#include <string>
#include <vector>
#include <binaryen-c.h>

static BinaryenExpressionRef build_sea_of_blocks(BinaryenModuleRef m,
                                                 int block_num) {
    std::vector<std::string> labels;
    labels.reserve(block_num);
    std::vector<const char *> label_ptrs;
    label_ptrs.reserve(block_num);
    for (auto i = 0; i < block_num; ++i) {
        labels.push_back(std::to_string(i));
        label_ptrs.push_back(labels[i].c_str());
    }
    BinaryenExpressionRef block_exprs[] = {
            BinaryenSwitch(m, label_ptrs.data(), block_num, label_ptrs[0],
                           BinaryenGetLocal(m, 0, BinaryenTypeInt32()), nullptr),
            BinaryenUnreachable(m)};
    for (auto i = 0; i < block_num; ++i) {
        block_exprs[0] =
                BinaryenBlock(m, label_ptrs[i], block_exprs, 2, BinaryenTypeNone());
        block_exprs[1] =
                BinaryenSetLocal(m, 1, BinaryenConst(m, BinaryenLiteralInt32(i)));
    }
    block_exprs[0] =
            BinaryenBlock(m, nullptr, block_exprs, 2, BinaryenTypeNone());
    block_exprs[1] = BinaryenGetLocal(m, 1, BinaryenTypeInt32());
    return BinaryenBlock(m, nullptr, block_exprs, 2, BinaryenTypeInt32());
}

int main() {
    auto m = BinaryenModuleCreate();
    auto i32 = BinaryenTypeInt32();
    auto ftype = BinaryenAddFunctionType(m, "ftype", i32, &i32, 1);
    auto expr = build_sea_of_blocks(m, 10000000);
    BinaryenAddFunction(m, "f", ftype, &i32, 1, expr);
    std::cout << "Starting validation" << std::endl;
    std::cout << BinaryenModuleValidate(m);
    BinaryenModuleDispose(m);
    return 0;
}