Add x86_64 compilation for arithmetic expressionsv0.10

6 files changed, 191 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index b1d8597..581dc1a 100644
--- a/Makefile
+++ b/Makefile
@@ -52,6 +52,12 @@ tests: $(BIN)
         # ./$(BIN) examples/types.bdl | diff tests/types_expected.txt -
         # ./$(BIN) examples/variables.bdl | diff tests/variables_expected.txt -
 
+run: $(BIN)
+        $(BIN) example.bdl > build/example.asm
+        nasm -felf64 build/example.asm -o build/example.o
+        ld build/example.o -o build/example
+        @./build/example
+
 # Remove build directory.
 clean:
         rm -rf $(BUILD_DIR)
diff --git a/README.md b/README.md
index cdb30a8..b5681c8 100644
--- a/README.md
+++ b/README.md
@@ -75,6 +75,7 @@ program       :  <statement>* EOF
 - [An Incremental Approach to Compiler Construction][ghuloum11]
 - [Make-A-Lisp Guide][mal]
 - [An Introduction to Scheme and its Implementation][intro-to-scheme-and-imp]
+- [Scheme to C][scheme-to-c]
 
 [sicp]: https://mitpress.mit.edu/sites/default/files/sicp/index.html
 [crafting-interpreters]: https://craftinginterpreters.com/
@@ -83,3 +84,4 @@ program       :  <statement>* EOF
 [ghuloum11]: http://scheme2006.cs.uchicago.edu/11-ghuloum.pdf
 [mal]: https://github.com/kanaka/mal/blob/master/process/guide.md
 [intro-to-scheme-and-imp]: https://www.cs.utexas.edu/ftp/garbage/cs345/schintro-v14/schintro_toc.html#SEC271
+[scheme-to-c]: https://github.com/akeep/scheme-to-c
diff --git a/src/compiler.h b/src/compiler.h
new file mode 100644
index 0000000..3fed075
--- /dev/null
+++ b/src/compiler.h
@@ -0,0 +1,115 @@
+#ifndef BDL_COMPILER_H
+#define BDL_COMPILER_H
+
+
+#define PRELUDE_FILE "src/x86_64/prelude.asm"
+#define POSTLUDE_FILE "src/x86_64/postlude.asm"
+
+void compile_object(Object *obj);
+void compile_fixnum(Object *obj);
+void compile_proc_call(Object *obj);
+void compile(Root *roots);
+
+void
+emit_file(char *file_name) {
+    FILE *file = fopen(file_name, "r");
+    if (!file) {
+        fprintf(stderr, "error: couldn't open input file: %s\n", file_name);
+        exit(EXIT_FAILURE);
+    }
+    char buf[1024];
+    size_t n = 0;
+    while ((n = fread(&buf, 1, 1024, file)) > 0) {
+        fwrite(buf, 1, n, stdout);
+    }
+}
+
+void
+compile_fixnum(Object *obj) {
+    printf("    ;; -- compile_fixnum --\n");
+    printf("    mov     rax, %ld\n", obj->fixnum);
+    printf("    push    rax\n");
+    printf("    ;; --------------------\n");
+}
+
+typedef enum OpType {
+    OP_ADD,
+    OP_SUB,
+    OP_MUL,
+    OP_DIV,
+    OP_MOD,
+} OpType;
+
+void
+arithmetic_op(OpType type) {
+    printf("    ;; -- arithmetic_op --\n");
+    printf("    pop     rcx\n");
+    printf("    pop     rax\n");
+    switch (type) {
+        case OP_ADD: {
+            printf("    add     rax, rcx\n");
+        } break;
+        case OP_SUB: {
+            printf("    sub     rax, rcx\n");
+        } break;
+        case OP_MUL: {
+            printf("    mul     rcx\n");
+        } break;
+        case OP_DIV: {
+            printf("    mov     rdx, 0\n");
+            printf("    div     rcx\n");
+        } break;
+        case OP_MOD: {
+            printf("    mov     rdx, 0\n");
+            printf("    div     rcx\n");
+            printf("    mov     rax, rdx\n");
+        } break;
+    }
+    printf("    push    rax\n");
+    printf("    ;; -------------------\n");
+}
+
+void
+compile_proc_call(Object *obj) {
+    printf("    ;; -- compile_proc_call --\n");
+    OpType op;
+    if (sv_equal(&obj->head->text, &STRING("+"))) { op = OP_ADD;}
+    if (sv_equal(&obj->head->text, &STRING("-"))) { op = OP_SUB;}
+    if (sv_equal(&obj->head->text, &STRING("*"))) { op = OP_MUL;}
+    if (sv_equal(&obj->head->text, &STRING("/"))) { op = OP_DIV;}
+    if (sv_equal(&obj->head->text, &STRING("%"))) { op = OP_MOD;}
+    // TODO: Resolve function call.
+    Object *args = obj->tail;
+    // TODO: capture first operand in the accumulator. Number of arguments
+    // checking should have been handled in the parser.
+    compile_object(args->head);
+    args = args->tail;
+    while (args != NULL) {
+        compile_object(args->head);
+        args = args->tail;
+        arithmetic_op(op);
+    }
+    printf("    ;; -----------------------\n");
+}
+
+void
+compile_object(Object *obj) {
+    switch (obj->type) {
+        case OBJ_TYPE_FIXNUM: { compile_fixnum(obj); } break;
+        case OBJ_TYPE_PAIR: { compile_proc_call(obj); } break;
+        default: break;
+    }
+}
+
+void
+compile(Root *roots) {
+    emit_file(PRELUDE_FILE);
+    for (size_t i = 0; i < array_size(roots); i++) {
+        Object *root = roots[i];
+        compile_object(root);
+        // OBJ_PRINT(root);
+    }
+    emit_file(POSTLUDE_FILE);
+}
+
+#endif // BDL_COMPILER_H
diff --git a/src/main.c b/src/main.c
index 6a683a7..cf4bfa4 100644
--- a/src/main.c
+++ b/src/main.c
@@ -8,6 +8,7 @@
 #include "errors.c"
 #include "lexer.c"
 #include "parser.c"
+#include "compiler.h"
 
 void
 init(void) {
@@ -41,9 +42,10 @@ process_source(const StringView *source, const char *file_name) {
     }
     array_free(tokens);
 
-    // TODO: Semantic analysis.
     // TODO: Optimization.
-    // TODO: Compilation.
+
+    // Compilation.
+    compile(roots);
 
     // Free resources.
     free_objects();
diff --git a/src/x86_64/postlude.asm b/src/x86_64/postlude.asm
new file mode 100644
index 0000000..139c4e1
--- /dev/null
+++ b/src/x86_64/postlude.asm
@@ -0,0 +1,8 @@
+    ;; return the last value in the stack
+    pop     rdi
+    call    printdln
+
+    ; exit syscall
+    mov     rax, 60
+    xor     rdi, rdi
+    syscall
diff --git a/src/x86_64/prelude.asm b/src/x86_64/prelude.asm
new file mode 100644
index 0000000..788b8e9
--- /dev/null
+++ b/src/x86_64/prelude.asm
@@ -0,0 +1,56 @@
+printdln:
+        sub     rsp, 40
+        mov     BYTE [rsp+31], 10
+        test    rdi, rdi
+        jne     .L2
+        mov     BYTE [rsp+30], 48
+        mov     eax, 30
+        mov     r8d, 2
+.L3:
+        lea     rsi, [rsp+rax]
+        mov     rdx, r8
+        ;; write syscall (Linux)
+        mov     rdi, 1
+        mov     rax, 1
+        syscall
+        add     rsp, 40
+        ret
+.L2:
+        mov     r10d, 1
+        js      .L12
+.L4:
+        mov     r8d, 1
+        lea     r9, [rsp+31]
+        mov     rsi, -3689348814741910323
+.L5:
+        mov     rax, rdi
+        mov     rcx, r9
+        mul     rsi
+        sub     rcx, r8
+        shr     rdx, 3
+        lea     rax, [rdx+rdx*4]
+        add     rax, rax
+        sub     rdi, rax
+        mov     rax, r8
+        add     r8, 1
+        add     edi, 48
+        mov     BYTE [rcx], dil
+        mov     rdi, rdx
+        test    rdx, rdx
+        jne     .L5
+        cmp     r10d, -1
+        jne     .L10
+        not     r8
+        mov     BYTE [rsp+32+r8], 45
+        lea     r8, [rax+2]
+.L10:
+        mov     eax, 32
+        sub     rax, r8
+        jmp     .L3
+.L12:
+        neg     rdi
+        mov     r10d, -1
+        jmp     .L4
+
+global  _start
+_start: