+
+/*
+ * mono_peephole_ins:
+ *
+ * Perform some architecture independent peephole optimizations.
+ */
+void
+mono_peephole_ins (MonoBasicBlock *bb, MonoInst *ins)
+{
+ MonoInst *last_ins = ins->prev;
+
+ switch (ins->opcode) {
+ case OP_MUL_IMM:
+ /* remove unnecessary multiplication with 1 */
+ if (ins->inst_imm == 1) {
+ if (ins->dreg != ins->sreg1)
+ ins->opcode = OP_MOVE;
+ else
+ MONO_DELETE_INS (bb, ins);
+ }
+ break;
+ case OP_LOAD_MEMBASE:
+ case OP_LOADI4_MEMBASE:
+ /*
+ * Note: if reg1 = reg2 the load op is removed
+ *
+ * OP_STORE_MEMBASE_REG reg1, offset(basereg)
+ * OP_LOAD_MEMBASE offset(basereg), reg2
+ * -->
+ * OP_STORE_MEMBASE_REG reg1, offset(basereg)
+ * OP_MOVE reg1, reg2
+ */
+ if (last_ins &&
+ (((ins->opcode == OP_LOADI4_MEMBASE) && (last_ins->opcode == OP_STOREI4_MEMBASE_REG)) ||
+ ((ins->opcode == OP_LOAD_MEMBASE) && (last_ins->opcode == OP_STORE_MEMBASE_REG))) &&
+ ins->inst_basereg == last_ins->inst_destbasereg &&
+ ins->inst_offset == last_ins->inst_offset) {
+ if (ins->dreg == last_ins->sreg1) {
+ MONO_DELETE_INS (bb, ins);
+ break;
+ } else {
+ ins->opcode = OP_MOVE;
+ ins->sreg1 = last_ins->sreg1;
+ }
+
+ /*
+ * Note: reg1 must be different from the basereg in the second load
+ * Note: if reg1 = reg2 is equal then second load is removed
+ *
+ * OP_LOAD_MEMBASE offset(basereg), reg1
+ * OP_LOAD_MEMBASE offset(basereg), reg2
+ * -->
+ * OP_LOAD_MEMBASE offset(basereg), reg1
+ * OP_MOVE reg1, reg2
+ */
+ } if (last_ins && (last_ins->opcode == OP_LOADI4_MEMBASE
+ || last_ins->opcode == OP_LOAD_MEMBASE) &&
+ ins->inst_basereg != last_ins->dreg &&
+ ins->inst_basereg == last_ins->inst_basereg &&
+ ins->inst_offset == last_ins->inst_offset) {
+
+ if (ins->dreg == last_ins->dreg) {
+ MONO_DELETE_INS (bb, ins);
+ } else {
+ ins->opcode = OP_MOVE;
+ ins->sreg1 = last_ins->dreg;
+ }
+
+ //g_assert_not_reached ();
+
+#if 0
+ /*
+ * OP_STORE_MEMBASE_IMM imm, offset(basereg)
+ * OP_LOAD_MEMBASE offset(basereg), reg
+ * -->
+ * OP_STORE_MEMBASE_IMM imm, offset(basereg)
+ * OP_ICONST reg, imm
+ */
+ } else if (last_ins && (last_ins->opcode == OP_STOREI4_MEMBASE_IMM
+ || last_ins->opcode == OP_STORE_MEMBASE_IMM) &&
+ ins->inst_basereg == last_ins->inst_destbasereg &&
+ ins->inst_offset == last_ins->inst_offset) {
+ ins->opcode = OP_ICONST;
+ ins->inst_c0 = last_ins->inst_imm;
+ g_assert_not_reached (); // check this rule
+#endif
+ }
+ break;
+ case OP_LOADI1_MEMBASE:
+ case OP_LOADU1_MEMBASE:
+ /*
+ * Note: if reg1 = reg2 the load op is removed
+ *
+ * OP_STORE_MEMBASE_REG reg1, offset(basereg)
+ * OP_LOAD_MEMBASE offset(basereg), reg2
+ * -->
+ * OP_STORE_MEMBASE_REG reg1, offset(basereg)
+ * OP_MOVE reg1, reg2
+ */
+ if (last_ins && (last_ins->opcode == OP_STOREI1_MEMBASE_REG) &&
+ ins->inst_basereg == last_ins->inst_destbasereg &&
+ ins->inst_offset == last_ins->inst_offset) {
+ ins->opcode = (ins->opcode == OP_LOADI1_MEMBASE) ? OP_PCONV_TO_I1 : OP_PCONV_TO_U1;
+ ins->sreg1 = last_ins->sreg1;
+ }
+ break;
+ case OP_LOADI2_MEMBASE:
+ case OP_LOADU2_MEMBASE:
+ /*
+ * Note: if reg1 = reg2 the load op is removed
+ *
+ * OP_STORE_MEMBASE_REG reg1, offset(basereg)
+ * OP_LOAD_MEMBASE offset(basereg), reg2
+ * -->
+ * OP_STORE_MEMBASE_REG reg1, offset(basereg)
+ * OP_MOVE reg1, reg2
+ */
+ if (last_ins && (last_ins->opcode == OP_STOREI2_MEMBASE_REG) &&
+ ins->inst_basereg == last_ins->inst_destbasereg &&
+ ins->inst_offset == last_ins->inst_offset) {
+#if SIZEOF_REGISTER == 8
+ ins->opcode = (ins->opcode == OP_LOADI2_MEMBASE) ? OP_PCONV_TO_I2 : OP_PCONV_TO_U2;
+#else
+ /* The definition of OP_PCONV_TO_U2 is wrong */
+ ins->opcode = (ins->opcode == OP_LOADI2_MEMBASE) ? OP_PCONV_TO_I2 : OP_ICONV_TO_U2;
+#endif
+ ins->sreg1 = last_ins->sreg1;
+ }
+ break;
+ case OP_MOVE:
+ case OP_FMOVE:
+ /*
+ * Removes:
+ *
+ * OP_MOVE reg, reg
+ */
+ if (ins->dreg == ins->sreg1) {
+ MONO_DELETE_INS (bb, ins);
+ break;
+ }
+ /*
+ * Removes:
+ *
+ * OP_MOVE sreg, dreg
+ * OP_MOVE dreg, sreg
+ */
+ if (last_ins && last_ins->opcode == OP_MOVE &&
+ ins->sreg1 == last_ins->dreg &&
+ ins->dreg == last_ins->sreg1) {
+ MONO_DELETE_INS (bb, ins);
+ }
+ break;
+ case OP_NOP:
+ MONO_DELETE_INS (bb, ins);
+ break;
+ }
+}
+