diff options
Diffstat (limited to 'submit/RegisterAllocator.java')
| -rw-r--r-- | submit/RegisterAllocator.java | 211 |
1 files changed, 119 insertions, 92 deletions
diff --git a/submit/RegisterAllocator.java b/submit/RegisterAllocator.java index ce18b2b..161435d 100644 --- a/submit/RegisterAllocator.java +++ b/submit/RegisterAllocator.java @@ -15,112 +15,139 @@ import java.util.Set; */ public final class RegisterAllocator { - // True if t is used - private final boolean[] t = new boolean[10]; - private final boolean[] s = new boolean[8]; - private final Set<String> used = new HashSet<>(); + // True if t is used + private final boolean[] t = new boolean[10]; + private final boolean[] s = new boolean[8]; + private final Set<String> used = new HashSet<>(); - public RegisterAllocator() { - clearAll(); - } + public RegisterAllocator() { clearAll(); } - public String getT() { - for (int i = 0; i < t.length; ++i) { - if (!t[i]) { - t[i] = true; - String str = "$t" + i; - used.add(str); - return str; - } - } - return null; + public String getRegisterOrLoadIntoRegister(MIPSResult result, + StringBuilder code) { + if (result.getRegister() != null) { + return result.getRegister(); } + String reg = result.getAddress(); + return this.loadIntoRegister(result, code, reg); + } -// public String getS() { -// for (int i = 0; i < s.length; ++i) { -// if (!s[i]) { -// s[i] = true; -// String str = "$s" + i; -// used.add(str); -// return str; -// } -// } -// return null; -// } - - // Returns the number of bytes used to save the registers - public int saveRestore(StringBuilder code, int baseOffset, boolean s_or_t, boolean save) { - boolean[] r = s; - String prefix = "$s"; - if (!s_or_t) { - r = t; - prefix = "$t"; - } - String instruction = "sw"; - if (!save) { - instruction = "lw"; - } - int offset = 0; - for (int i = 0; i < r.length; ++i) { - if (r[i]) { - offset -= 4; - String str = prefix + i; - code.append(instruction).append(" ").append(str).append(" ").append(offset-baseOffset).append("($sp)\n"); - } - } - return -offset; - } + public String loadIntoRegister(MIPSResult result, StringBuilder code, + String register) { + return loadIntoRegisterWithOffset(result, code, register, 0); + } + + public String loadIntoRegisterWithOffset(MIPSResult result, + StringBuilder code, String register, + int offset) { + code.append( + String.format("lw %s %d(%s)\n", register, offset, result.getAddress())); -// public int saveS(StringBuilder code, int baseOffset) { -// return saveRestore(code, baseOffset, true, true); -// } + return register; + } - public int saveT(StringBuilder code, int baseOffset) { - return saveRestore(code, baseOffset, false, true); + public String getT() { + for (int i = 0; i < t.length; ++i) { + if (!t[i]) { + t[i] = true; + String str = "$t" + i; + used.add(str); + return str; + } } + return null; + } -// public int restoreS(StringBuilder code, int baseOffset) { -// return saveRestore(code, baseOffset, true, false); -// } + // public String getS() { + // for (int i = 0; i < s.length; ++i) { + // if (!s[i]) { + // s[i] = true; + // String str = "$s" + i; + // used.add(str); + // return str; + // } + // } + // return null; + // } - public int restoreT(StringBuilder code, int baseOffset) { - return saveRestore(code, baseOffset, false, false); + // Returns the number of bytes used to save the registers + public int saveRestore(StringBuilder code, int baseOffset, boolean s_or_t, + boolean save) { + boolean[] r = s; + String prefix = "$s"; + if (!s_or_t) { + r = t; + prefix = "$t"; } - - public List<String> getUsed() { - return new ArrayList<>(used); + String instruction = "sw"; + if (!save) { + instruction = "lw"; } - - /** - * Any time you call this method you should seriously consider adding a - * corresponding clear() call. - * - * @return - */ - public String getAny() { -// String availS = getS(); -// if (availS != null) { -// return availS; -// } - String t = getT(); - if (t == null) { - throw new RuntimeException("Out of registers"); - } - return t; + int offset = 0; + for (int i = 0; i < r.length; ++i) { + if (r[i]) { + offset -= 4; + String str = prefix + i; + code.append(instruction) + .append(" ") + .append(str) + .append(" ") + .append(offset - baseOffset) + .append("($sp)\n"); + } } + return -offset; + } + + // public int saveS(StringBuilder code, int baseOffset) { + // return saveRestore(code, baseOffset, true, true); + // } - public void clear(String reg) { - if (reg.charAt(1) == 's') { - s[Integer.parseInt(reg.substring(2))] = false; - } else if (reg.charAt(1) == 't') { - t[Integer.parseInt(reg.substring(2))] = false; - } else { - throw new RuntimeException("Unexpected register in clear"); - } + public int saveT(StringBuilder code, int baseOffset) { + return saveRestore(code, baseOffset, false, true); + } + + // public int restoreS(StringBuilder code, int baseOffset) { + // return saveRestore(code, baseOffset, true, false); + // } + + public int restoreT(StringBuilder code, int baseOffset) { + return saveRestore(code, baseOffset, false, false); + } + + public List<String> getUsed() { return new ArrayList<>(used); } + + /** + * Any time you call this method you should seriously consider adding a + * corresponding clear() call. + * + * @return + */ + public String getAny() { + // String availS = getS(); + // if (availS != null) { + // return availS; + // } + String t = getT(); + if (t == null) { + throw new RuntimeException("Out of registers"); } + return t; + } - public void clearAll() { - Arrays.fill(t, false); - Arrays.fill(s, false); + public void clear(String reg) { + if (reg == null) + return; + if (reg.charAt(1) == 's') { + s[Integer.parseInt(reg.substring(2))] = false; + } else if (reg.charAt(1) == 't') { + t[Integer.parseInt(reg.substring(2))] = false; + } else { + throw new RuntimeException("Unexpected register in clear"); } + } + + public void clearAll() { + Arrays.fill(t, false); + Arrays.fill(s, false); + } } |