Added some code to reverse evaluation order of assignment operators when possible

diff --git a/lang/cem/cemcom.ansi/eval.c b/lang/cem/cemcom.ansi/eval.c
index 4f192ea..1b8b3da 100644 (file)
--- a/lang/cem/cemcom.ansi/eval.c
+++ b/lang/cem/cemcom.ansi/eval.c
@@ -392,6 +392,7 @@ EVAL(expr, val, code, true_label, false_label)
                        arith tmp = 0;
                        int compl;      /* Complexity of left operand */
                        int newcode = left->ex_type->tp_size > 0; /* CJ */
+                       int right_done = 0;
 #ifndef NOBITFIELD
                        if (left->ex_type->tp_fund == FIELD) {
                                eval_field(expr, gencode);
@@ -400,16 +401,32 @@ EVAL(expr, val, code, true_label, false_label)
 #endif NOBITFIELD
                        if (newcode && left->ex_class == Value) {
                                compl = 0; /* Value */
-                               load_val(left, RVAL);
                        }
-                       else
-                       if (left->ex_depth == 1 &&
+                       else if (left->ex_depth == 1 &&
                            !(left->ex_flags & EX_SIDEEFFECTS)) {
                                compl = 1;
+                       }
+                       else    compl = 2;
+
+                       /* evaluate right-hand side first when possible,
+                          but not for POSTINCR or PLUSPLUS, because then
+                          we might miss a chance for increment instructions.
+                       */
+                       if (compl != 2 &&
+                           tp->tp_fund != POINTER &&
+                           (oper == PLUSAB || oper == TIMESAB ||
+                            oper == ANDAB || oper == XORAB || oper == ORAB)) {
+                               right_done = 1;
+                               EVAL(right, RVAL, newcode, NO_LABEL, NO_LABEL);
+                       }
+                       if (compl == 0) {
+                               load_val(left, RVAL);
+                       }
+                       else
+                       if (compl == 1) {
                                EVAL(left, RVAL, newcode, NO_LABEL, NO_LABEL);
                        }
                        else {
-                               compl = 2; /* otherwise */
                                EVAL(left, LVAL, newcode, NO_LABEL, NO_LABEL);
                                if (newcode) {
                                        tmp = LocalPtrVar();
@@ -424,7 +441,9 @@ EVAL(expr, val, code, true_label, false_label)
                                        C_dup(ATW(left->ex_type->tp_size));
                                conversion(left->ex_type, tp);
                        }
-                       EVAL(right, RVAL, newcode, NO_LABEL, NO_LABEL);
+                       if (! right_done) {
+                               EVAL(right, RVAL, newcode, NO_LABEL, NO_LABEL);
+                       }
                        if (newcode) {
                                int dupval = gencode && oper != POSTINCR &&
                                                oper != POSTDECR;

diff --git a/lang/cem/cemcom/eval.c b/lang/cem/cemcom/eval.c
index 6478a2a..ce0e957 100644 (file)
--- a/lang/cem/cemcom/eval.c
+++ b/lang/cem/cemcom/eval.c
@@ -383,6 +383,7 @@ EVAL(expr, val, code, true_label, false_label)
                        arith tmp;
                        int compl;      /* Complexity of left operand */
                        int newcode = left->ex_type->tp_size > 0; /* CJ */
+                       int right_done = 0;
 #ifndef NOBITFIELD
                        if (left->ex_type->tp_fund == FIELD) {
                                eval_field(expr, gencode);
@@ -391,16 +392,32 @@ EVAL(expr, val, code, true_label, false_label)
 #endif NOBITFIELD
                        if (newcode && left->ex_class == Value) {
                                compl = 0; /* Value */
-                               load_val(left, RVAL);
                        }
-                       else
-                       if (left->ex_depth == 1 &&
+                       else if (left->ex_depth == 1 &&
                            !(left->ex_flags & EX_SIDEEFFECTS)) {
                                compl = 1;
+                       }
+                       else    compl = 2;
+
+                       /* evaluate right-hand side first when possible,
+                          but not for POSTINCR or PLUSPLUS, because then
+                          we might miss a chance for increment instructions.
+                       */
+                       if (compl != 2 &&
+                           tp->tp_fund != POINTER &&
+                           (oper == PLUSAB || oper == TIMESAB ||
+                            oper == ANDAB || oper == XORAB || oper == ORAB)) {
+                               right_done = 1;
+                               EVAL(right, RVAL, newcode, NO_LABEL, NO_LABEL);
+                       }
+                       if (compl == 0) {
+                               load_val(left, RVAL);
+                       }
+                       else
+                       if (compl == 1) {
                                EVAL(left, RVAL, newcode, NO_LABEL, NO_LABEL);
                        }
                        else {
-                               compl = 2; /* otherwise */
                                EVAL(left, LVAL, newcode, NO_LABEL, NO_LABEL);
                                if (newcode) {
                                        tmp = LocalPtrVar();
@@ -415,7 +432,9 @@ EVAL(expr, val, code, true_label, false_label)
                                        C_dup(ATW(left->ex_type->tp_size));
                                conversion(left->ex_type, tp);
                        }
-                       EVAL(right, RVAL, newcode, NO_LABEL, NO_LABEL);
+                       if (! right_done) {
+                               EVAL(right, RVAL, newcode, NO_LABEL, NO_LABEL);
+                       }
                        if (newcode) {
                                int dupval = gencode && oper != POSTINCR &&
                                                oper != POSTDECR;