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-rw-r--r--soft-fp/op-common.h44
1 files changed, 44 insertions, 0 deletions
diff --git a/soft-fp/op-common.h b/soft-fp/op-common.h
index 232604e74a..3abafa14a8 100644
--- a/soft-fp/op-common.h
+++ b/soft-fp/op-common.h
@@ -766,3 +766,47 @@ do { \
q = n / d, r = n % d; \
} while (0)
+
+/* A restoring bit-by-bit division primitive. */
+
+#define _FP_DIV_MEAT_N_loop(fs, wc, R, X, Y) \
+ do { \
+ int count = _FP_WFRACBITS_##fs; \
+ _FP_FRAC_DECL_##wc (u); \
+ _FP_FRAC_DECL_##wc (v); \
+ _FP_FRAC_COPY_##wc (u, X); \
+ _FP_FRAC_COPY_##wc (v, Y); \
+ _FP_FRAC_SET_##wc (R, _FP_ZEROFRAC_##wc); \
+ /* Normalize U and V. */ \
+ _FP_FRAC_SLL_##wc (u, _FP_WFRACXBITS_##fs); \
+ _FP_FRAC_SLL_##wc (v, _FP_WFRACXBITS_##fs); \
+ /* First round. Since the operands are normalized, either the \
+ first or second bit will be set in the fraction. Produce a \
+ normalized result by checking which and adjusting the loop \
+ count and exponent accordingly. */ \
+ if (_FP_FRAC_GE_1 (u, v)) \
+ { \
+ _FP_FRAC_SUB_##wc (u, u, v); \
+ _FP_FRAC_LOW_##wc (R) |= 1; \
+ count--; \
+ } \
+ else \
+ R##_e--; \
+ /* Subsequent rounds. */ \
+ do { \
+ int msb = (_FP_WS_TYPE) _FP_FRAC_HIGH_##wc (u) < 0; \
+ _FP_FRAC_SLL_##wc (u, 1); \
+ _FP_FRAC_SLL_##wc (R, 1); \
+ if (msb || _FP_FRAC_GE_1 (u, v)) \
+ { \
+ _FP_FRAC_SUB_##wc (u, u, v); \
+ _FP_FRAC_LOW_##wc (R) |= 1; \
+ } \
+ } while (--count > 0); \
+ /* If there's anything left in U, the result is inexact. */ \
+ _FP_FRAC_LOW_##wc (R) |= !_FP_FRAC_ZEROP_##wc (u); \
+ } while (0)
+
+#define _FP_DIV_MEAT_1_loop(fs, R, X, Y) _FP_DIV_MEAT_N_loop (fs, 1, R, X, Y)
+#define _FP_DIV_MEAT_2_loop(fs, R, X, Y) _FP_DIV_MEAT_N_loop (fs, 2, R, X, Y)
+#define _FP_DIV_MEAT_4_loop(fs, R, X, Y) _FP_DIV_MEAT_N_loop (fs, 4, R, X, Y)