libgcc/

[pf3gnuchains/gcc-fork.git] / libgcc / config / libbid / bid128_scalb.c

diff --git a/libgcc/config/libbid/bid128_scalb.c b/libgcc/config/libbid/bid128_scalb.c
index 8f85d3c..fa354b1 100644 (file)
--- a/libgcc/config/libbid/bid128_scalb.c
+++ b/libgcc/config/libbid/bid128_scalb.c
@@ -34,53 +34,68 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
 
 
 
-BID128_FUNCTION_ARG128_ARGTYPE2(__bid128_scalb, x, int, n)
+BID128_FUNCTION_ARG128_ARGTYPE2 (bid128_scalb, x, int, n)
 
-UINT128 CX, CX2, CX8, res;
-  UINT64 sign_x;
-  int exponent_x, rmode;
+     UINT128 CX, CX2, CX8, res;
+     SINT64 exp64;
+     UINT64 sign_x;
+     int exponent_x, rmode;
 
   // unpack arguments, check for NaN or Infinity
-  if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) {
+if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) {
     // x is Inf. or NaN or 0
-    res.w[1] = x.w[1];
-    res.w[0] = x.w[0];
-    BID_RETURN (res);
-  }
+#ifdef SET_STATUS_FLAGS
+if ((x.w[1] & SNAN_MASK64) == SNAN_MASK64)     // y is sNaN
+  __set_status_flags (pfpsf, INVALID_EXCEPTION);
+#endif
+res.w[1] = CX.w[1] & QUIET_MASK64;
+res.w[0] = CX.w[0];
+if (!CX.w[1]) {
+       exp64 = (SINT64) exponent_x + (SINT64) n;
+          if(exp64<0) exp64=0;
+          if(exp64>MAX_DECIMAL_EXPONENT_128) exp64=MAX_DECIMAL_EXPONENT_128;
+       exponent_x = exp64;
+  get_BID128_very_fast (&res, sign_x, exponent_x, CX);
+}
+BID_RETURN (res);
+}
 
-  exponent_x += n;
+exp64 = (SINT64) exponent_x + (SINT64) n;
+exponent_x = exp64;
 
-  if ((UINT32) exponent_x <= MAX_DECIMAL_EXPONENT_128) {
-    get_BID128_very_fast (&res, sign_x, exponent_x, CX);
-    BID_RETURN (res);
-  }
+if ((UINT32) exponent_x <= MAX_DECIMAL_EXPONENT_128) {
+  get_BID128_very_fast (&res, sign_x, exponent_x, CX);
+  BID_RETURN (res);
+}
   // check for overflow
-  if (exponent_x > MAX_DECIMAL_EXPONENT_128) {
-    if (CX.w[1] < 0x314dc6448d93ull) {
-      // try to normalize coefficient
-      do {
-       CX8.w[1] = (CX.w[1] << 3) | (CX.w[0] >> 61);
-       CX8.w[0] = CX.w[0] << 3;
-       CX2.w[1] = (CX.w[1] << 1) | (CX.w[0] >> 63);
-       CX2.w[0] = CX.w[0] << 1;
-       __add_128_128 (CX, CX2, CX8);
-
-       exponent_x--;
-      }
-      while (CX.w[1] < 0x314dc6448d93ull
-            && exponent_x > MAX_DECIMAL_EXPONENT_128);
-
-      if (exponent_x <= MAX_DECIMAL_EXPONENT_128) {
-       get_BID128_very_fast (&res, sign_x, exponent_x, CX);
-       BID_RETURN (res);
-      }
+if (exp64 > MAX_DECIMAL_EXPONENT_128) {
+  if (CX.w[1] < 0x314dc6448d93ull) {
+    // try to normalize coefficient
+    do {
+      CX8.w[1] = (CX.w[1] << 3) | (CX.w[0] >> 61);
+      CX8.w[0] = CX.w[0] << 3;
+      CX2.w[1] = (CX.w[1] << 1) | (CX.w[0] >> 63);
+      CX2.w[0] = CX.w[0] << 1;
+      __add_128_128 (CX, CX2, CX8);
+
+      exponent_x--;
+      exp64--;
     }
+    while (CX.w[1] < 0x314dc6448d93ull
+          && exp64 > MAX_DECIMAL_EXPONENT_128);
+
   }
+  if (exp64 <= MAX_DECIMAL_EXPONENT_128) {
+    get_BID128_very_fast (&res, sign_x, exponent_x, CX);
+    BID_RETURN (res);
+  } else
+    exponent_x = 0x7fffffff;   // overflow
+}
   // exponent < 0
   // the BID pack routine will round the coefficient
-  rmode = rnd_mode;
-  get_BID128 (&res, sign_x, exponent_x, CX, (unsigned int *) &rmode,
-             pfpsf);
-  BID_RETURN (res);
+rmode = rnd_mode;
+get_BID128 (&res, sign_x, exponent_x, CX, (unsigned int *) &rmode,
+           pfpsf);
+BID_RETURN (res);
 
 }