Initial commit

format.c

@@ -0,0 +1,168 @@
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <decode.h>
+
+
+#define DECODE_TABLE_STRTAB1
+static const char* _mnemonic_str =
+#include <decode-table.inc>
+;
+#undef DECODE_TABLE_STRTAB1
+
+#define DECODE_TABLE_STRTAB2
+static const uint16_t _mnemonic_offs[] = {
+#include <decode-table.inc>
+};
+#undef DECODE_TABLE_STRTAB2
+
+static
+void
+instr_format_decimal(char** cur, uint32_t value)
+{
+    char buffer[32];
+    size_t buf_idx = sizeof(buffer) - 1;
+    if (value == 0)
+    {
+        buffer[buf_idx] = '0';
+    }
+    else
+    {
+        while (value > 0)
+        {
+            uint32_t digit = value % 10;
+            buffer[buf_idx--] = '0' + digit;
+            value /= 10;
+        }
+        buf_idx++;
+    }
+
+    size_t length = sizeof(buffer) - buf_idx;
+    __builtin_memcpy(*cur, buffer + buf_idx, length);
+    *cur += length;
+}
+
+static
+void
+instr_format_hex(char** cur, size_t value)
+{
+    char buffer[32];
+    size_t buf_idx = sizeof(buffer) - 1;
+    if (value == 0)
+    {
+        buffer[buf_idx] = '0';
+    }
+    else
+    {
+        while (value > 0)
+        {
+            uint32_t nibble = value & 0xf;
+            buffer[buf_idx--] = "0123456789abcdef"[nibble];
+            value >>= 4;
+        }
+        buf_idx++;
+    }
+    buffer[--buf_idx] = 'x';
+    buffer[--buf_idx] = '0';
+
+    size_t length = sizeof(buffer) - buf_idx;
+    __builtin_memcpy(*cur, buffer + buf_idx, length);
+    *cur += length;
+}
+
+void
+instr_format(const Instr* instr, char buffer[128])
+{
+    char* cur = buffer;
+    *(cur++) = '[';
+
+    const char* mnemonic = &_mnemonic_str[_mnemonic_offs[instr->type]];
+    while (*mnemonic)
+    {
+        *(cur++) = *(mnemonic++);
+    }
+
+    if (instr->width != 0)
+    {
+        *(cur++) = '_';
+        instr_format_decimal(&cur, instr->width);
+    }
+
+    for (int i = 0; i < 4; i++)
+    {
+        const struct Operand* operand = &instr->operands[i];
+        if (operand->type == OT_NONE)
+        {
+            break;
+        }
+
+        __builtin_memcpy(cur, " REG IMM MEM" + operand->type * 4 - 4, 4);
+        cur += 4;
+        instr_format_decimal(&cur, operand->size);
+        *(cur++) = ':';
+
+        switch (operand->type)
+        {
+            size_t immediate;
+            case OT_REG:
+                instr_format_decimal(&cur, reg_index(operand->reg));
+                break;
+            case OT_IMM:
+                immediate = instr->immediate;
+                if (operand->size == 1)
+                {
+                    immediate &= 0xff;
+                }
+                else if (operand->size == 2)
+                {
+                    immediate &= 0xffff;
+                }
+#if defined(ARCH_X86_64)
+                else if (operand->size == 4)
+                {
+                    immediate &= 0xffffffff;
+                }
+#endif
+                instr_format_hex(&cur, immediate);
+                break;
+            case OT_MEM:
+                if (!reg_is_none(operand->reg))
+                {
+                    instr_format_decimal(&cur, reg_index(operand->reg));
+                    *(cur++) = ':';
+                }
+                if (instr->scale != 0)
+                {
+                    uint8_t scale = 1 << (instr->scale - 1);
+                    instr_format_decimal(&cur, scale);
+                    *(cur++) = '*';
+                    instr_format_decimal(&cur, reg_index(instr->sreg));
+                    *(cur++) = ':';
+                }
+                if (instr->disp < 0)
+                {
+                    *(cur++) = '-';
+                    instr_format_hex(&cur, -instr->disp);
+                }
+                else
+                {
+                    instr_format_hex(&cur, instr->disp);
+                }
+                break;
+            case OT_NONE:
+            default:
+                break;
+        }
+    }
+
+    *(cur++) = ']';
+    *(cur++) = '\0';
+
+#ifndef NDEBUG
+    if (cur - buffer > 128)
+    {
+        __builtin_trap();
+    }
+#endif
+}