1/*===-- calc.c - tool for testing libLLVM and llvm-c API ------------------===*\
2|*                                                                            *|
3|*                     The LLVM Compiler Infrastructure                       *|
4|*                                                                            *|
5|* This file is distributed under the University of Illinois Open Source      *|
6|* License. See LICENSE.TXT for details.                                      *|
7|*                                                                            *|
8|*===----------------------------------------------------------------------===*|
9|*                                                                            *|
10|* This file implements the --calc command in llvm-c-test. --calc reads lines *|
11|* from stdin, parses them as a name and an expression in reverse polish      *|
12|* notation and prints a module with a function with the expression.          *|
13|*                                                                            *|
14\*===----------------------------------------------------------------------===*/
15
16#include "llvm-c-test.h"
17#include "llvm-c/Core.h"
18#include <stdio.h>
19#include <stdlib.h>
20#include <string.h>
21#include <assert.h>
22
23typedef LLVMValueRef (*binop_func_t)(LLVMBuilderRef, LLVMValueRef LHS,
24                                     LLVMValueRef RHS, const char *Name);
25
26static LLVMOpcode op_to_opcode(char op) {
27  switch (op) {
28  case '+': return LLVMAdd;
29  case '-': return LLVMSub;
30  case '*': return LLVMMul;
31  case '/': return LLVMSDiv;
32  case '&': return LLVMAnd;
33  case '|': return LLVMOr;
34  case '^': return LLVMXor;
35  }
36  assert(0 && "unknown operation");
37  return 0;
38}
39
40#define MAX_DEPTH 32
41
42static LLVMValueRef build_from_tokens(char **tokens, int ntokens,
43                                      LLVMBuilderRef builder,
44                                      LLVMValueRef param) {
45  LLVMValueRef stack[MAX_DEPTH];
46  int depth = 0;
47  int i;
48
49  for (i = 0; i < ntokens; i++) {
50    char tok = tokens[i][0];
51    switch (tok) {
52    case '+':
53    case '-':
54    case '*':
55    case '/':
56    case '&':
57    case '|':
58    case '^':
59      if (depth < 2) {
60        printf("stack underflow\n");
61        return NULL;
62      }
63
64      stack[depth - 2] = LLVMBuildBinOp(builder, op_to_opcode(tok),
65                                        stack[depth - 1], stack[depth - 2], "");
66      depth--;
67
68      break;
69
70    case '@': {
71      LLVMValueRef off;
72
73      if (depth < 1) {
74        printf("stack underflow\n");
75        return NULL;
76      }
77
78      off = LLVMBuildGEP(builder, param, &stack[depth - 1], 1, "");
79      stack[depth - 1] = LLVMBuildLoad(builder, off, "");
80
81      break;
82    }
83
84    default: {
85      char *end;
86      long val = strtol(tokens[i], &end, 0);
87      if (end[0] != '\0') {
88        printf("error parsing number\n");
89        return NULL;
90      }
91
92      if (depth >= MAX_DEPTH) {
93        printf("stack overflow\n");
94        return NULL;
95      }
96
97      stack[depth++] = LLVMConstInt(LLVMInt64Type(), val, 1);
98      break;
99    }
100    }
101  }
102
103  if (depth < 1) {
104    printf("stack underflow at return\n");
105    return NULL;
106  }
107
108  LLVMBuildRet(builder, stack[depth - 1]);
109
110  return stack[depth - 1];
111}
112
113static void handle_line(char **tokens, int ntokens) {
114  char *name = tokens[0];
115  LLVMValueRef param;
116  LLVMValueRef res;
117
118  LLVMModuleRef M = LLVMModuleCreateWithName(name);
119
120  LLVMTypeRef I64ty = LLVMInt64Type();
121  LLVMTypeRef I64Ptrty = LLVMPointerType(I64ty, 0);
122  LLVMTypeRef Fty = LLVMFunctionType(I64ty, &I64Ptrty, 1, 0);
123
124  LLVMValueRef F = LLVMAddFunction(M, name, Fty);
125  LLVMBuilderRef builder = LLVMCreateBuilder();
126  LLVMPositionBuilderAtEnd(builder, LLVMAppendBasicBlock(F, "entry"));
127
128  LLVMGetParams(F, &param);
129  LLVMSetValueName(param, "in");
130
131  res = build_from_tokens(tokens + 1, ntokens - 1, builder, param);
132  if (res) {
133    char *irstr = LLVMPrintModuleToString(M);
134    puts(irstr);
135    LLVMDisposeMessage(irstr);
136  }
137
138  LLVMDisposeBuilder(builder);
139
140  LLVMDisposeModule(M);
141}
142
143int calc(void) {
144
145  tokenize_stdin(handle_line);
146
147  return 0;
148}
149