more about genUnpackBits

[fw/sdcc] / src / mcs51 / gen.c

diff --git a/src/mcs51/gen.c b/src/mcs51/gen.c
index 14782781d018aace7ab1684ab7ecd6737f6b6364..c9b86b9725967ccc04255d6728639214d3f45a9e 100644 (file)
--- a/src/mcs51/gen.c
+++ b/src/mcs51/gen.c
@@ -2412,7 +2412,7 @@ static void
 saveRBank (int bank, iCode * ic, bool pushPsw)
 {
   int i;
-  int count = mcs51_nRegs + (pushPsw ? 1 : 0);
+  int count = 8 + ((mcs51_nRegs > 8) ? 1 : 0) + (pushPsw ? 1 : 0);
   asmop *aop = NULL;
   regs *r = NULL;
 
@@ -2435,7 +2435,7 @@ saveRBank (int bank, iCode * ic, bool pushPsw)
       emitcode ("mov", "%s,a", spname);
     }
 
-  for (i = 0; i < mcs51_nRegs; i++)
+  for (i = 0; i < 8; i++)
     {
       if (options.useXstack)
         {
@@ -2450,6 +2450,22 @@ saveRBank (int bank, iCode * ic, bool pushPsw)
                   regs8051[i].base, 8 * bank + regs8051[i].offset);
     }
 
+  if (mcs51_nRegs > 8)
+    {
+      if (options.useXstack)
+        {
+          emitcode ("mov", "a,bits");
+          emitcode ("movx", "@%s,a", r->name);
+          if (--count)
+            emitcode ("inc", "%s", r->name);
+        }
+      else
+        {
+          emitcode ("push", "bits");
+        }
+      BitBankUsed = 1;
+    }
+
   if (pushPsw)
     {
       if (options.useXstack)
@@ -2516,7 +2532,21 @@ unsaveRBank (int bank, iCode * ic, bool popPsw)
         }
     }
 
-  for (i = (mcs51_nRegs - 1); i >= 0; i--)
+  if (mcs51_nRegs > 8)
+    {
+      if (options.useXstack)
+        {
+          emitcode ("dec", "%s", r->name);
+          emitcode ("movx", "a,@%s", r->name);
+          emitcode ("mov", "bits,a");
+        }
+      else
+        {
+          emitcode ("pop", "bits");
+        }
+    }
+
+  for (i = 7; i >= 0; i--)
     {
       if (options.useXstack)
         {
@@ -8714,7 +8744,7 @@ static void
 shiftRLong (operand * left, int offl,
             operand * result, int sign)
 {
-  int isSameRegs=sameRegs(AOP(left),AOP(result));
+  int isSameRegs = sameRegs (AOP (left), AOP (result));
 
   if (isSameRegs && offl>1) {
     // we are in big trouble, but this shouldn't happen
@@ -9277,6 +9307,15 @@ genUnpackBits (operand * result, char *rname, int ptype, iCode *ifx)
       emitPtrByteGet (rname, ptype, FALSE);
       AccRsh (bstr);
       emitcode ("anl", "a,#0x%02x", ((unsigned char) -1) >> (8 - blen));
+      if (!SPEC_USIGN (etype))
+        {
+          /* signed bitfield */
+          symbol *tlbl = newiTempLabel (NULL);
+
+          emitcode ("jnb", "acc.%d,%05d$", blen - 1, tlbl->key + 100);
+          emitcode ("orl", "a,#0x%02x", (unsigned char) (0xff << blen));
+          emitcode ("", "%05d$:", tlbl->key + 100);
+        }
       aopPut (result, "a", offset++, isOperandVolatile (result, FALSE));
       goto finish;
     }
@@ -9296,15 +9335,36 @@ genUnpackBits (operand * result, char *rname, int ptype, iCode *ifx)
     {
       emitPtrByteGet (rname, ptype, FALSE);
       emitcode ("anl", "a,#0x%02x", ((unsigned char) -1) >> (8-rlen));
+      if (!SPEC_USIGN (etype))
+        {
+          /* signed bitfield */
+          symbol *tlbl = newiTempLabel (NULL);
+
+          emitcode ("jnb", "acc.%d,%05d$", blen - 1, tlbl->key + 100);
+          emitcode ("orl", "a,#0x%02x", (unsigned char) (0xff << rlen));
+          emitcode ("", "%05d$:", tlbl->key + 100);
+        }
       aopPut (result, "a", offset++, isOperandVolatile (result, FALSE));
     }
 
 finish:
   if (offset < rsize)
     {
+      char *source;
+
+      if (SPEC_USIGN (etype))
+        source = zero;
+      else
+        {
+          /* signed bitfield: sign extension with 0x00 or 0xff */
+          emitcode ("rlc", "a");
+          emitcode ("subb", "a,acc");
+
+          source = "a";
+        }
       rsize -= offset;
       while (rsize--)
-        aopPut (result, zero, offset++, isOperandVolatile (result, FALSE));
+        aopPut (result, source, offset++, isOperandVolatile (result, FALSE));
     }
 }