[Qemu-devel] [6097] target-ppc: use float_flag_divbyzero instead of checking the operands

[Aurelien Jarno <aurelien@aurel32.net>]

Revision: 6097
          http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=6097
Author:   aurel32
Date:     2008-12-18 22:44:21 +0000 (Thu, 18 Dec 2008)

Log Message:
-----------
target-ppc: use float_flag_divbyzero instead of checking the operands

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

Modified Paths:
--------------
    trunk/target-ppc/op_helper.c

Modified: trunk/target-ppc/op_helper.c
===================================================================
--- trunk/target-ppc/op_helper.c	2008-12-18 22:44:13 UTC (rev 6096)
+++ trunk/target-ppc/op_helper.c	2008-12-18 22:44:21 UTC (rev 6097)
@@ -697,7 +697,7 @@
     return ret;
 }
 
-static always_inline uint64_t float_zero_divide_excp (uint64_t arg1, uint64_t arg2)
+static always_inline void float_zero_divide_excp (void)
 {
     env->fpscr |= 1 << FPSCR_ZX;
     env->fpscr &= ~((1 << FPSCR_FR) | (1 << FPSCR_FI));
@@ -710,12 +710,7 @@
             helper_raise_exception_err(POWERPC_EXCP_PROGRAM,
                                        POWERPC_EXCP_FP | POWERPC_EXCP_FP_ZX);
         }
-    } else {
-        /* Set the result to infinity */
-        arg1 = ((arg1 ^ arg2) & 0x8000000000000000ULL);
-        arg1 |= 0x7FFULL << 52;
     }
-    return arg1;
 }
 
 static always_inline void float_overflow_excp (void)
@@ -969,7 +964,9 @@
             helper_raise_exception_err(env->exception_index, env->error_code);
     } else {
         int status = get_float_exception_flags(&env->fp_status);
-        if (status & float_flag_overflow) {
+        if (status & float_flag_divbyzero) {
+            float_zero_divide_excp();
+        } else if (status & float_flag_overflow) {
             float_overflow_excp();
         } else if (status & float_flag_underflow) {
             float_underflow_excp();
@@ -1086,14 +1083,9 @@
     } else if (unlikely(float64_is_infinity(farg1.d) && float64_is_infinity(farg2.d))) {
         /* Division of infinity by infinity */
         farg1.ll = fload_invalid_op_excp(POWERPC_EXCP_FP_VXIDI);
-    } else if (unlikely(!float64_is_nan(farg1.d) && float64_is_zero(farg2.d))) {
-        if (float64_is_zero(farg1.d)) {
-            /* Division of zero by zero */
-            farg1.ll = fload_invalid_op_excp(POWERPC_EXCP_FP_VXZDZ);
-        } else {
-            /* Division by zero */
-            farg1.ll = float_zero_divide_excp(farg1.d, farg2.d);
-        }
+    } else if (unlikely(float64_is_zero(farg1.d) && float64_is_zero(farg2.d))) {
+        /* Division of zero by zero */
+        farg1.ll = fload_invalid_op_excp(POWERPC_EXCP_FP_VXZDZ);
     } else {
         farg1.d = float64_div(farg1.d, farg2.d, &env->fp_status);
     }
@@ -1513,9 +1505,6 @@
     if (unlikely(float64_is_signaling_nan(farg.d))) {
         /* sNaN reciprocal */
         farg.ll = fload_invalid_op_excp(POWERPC_EXCP_FP_VXSNAN);
-    } else if (unlikely(float64_is_zero(farg.d))) {
-        /* Zero reciprocal */
-        farg.ll = float_zero_divide_excp(fone.d, farg.d);
     } else {
         farg.d = float64_div(fone.d, farg.d, &env->fp_status);
     }
@@ -1533,9 +1522,6 @@
     if (unlikely(float64_is_signaling_nan(farg.d))) {
         /* sNaN reciprocal */
         farg.ll = fload_invalid_op_excp(POWERPC_EXCP_FP_VXSNAN);
-    } else if (unlikely(float64_is_zero(farg.d))) {
-        /* Zero reciprocal */
-        farg.ll = float_zero_divide_excp(fone.d, farg.d);
     } else {
         farg.d = float64_div(fone.d, farg.d, &env->fp_status);
         f32 = float64_to_float32(farg.d, &env->fp_status);