[sh] Add flag_unsafe_math_optimizations to sincossf3

[Richard Sandiford]

builtins.c uses the following code to guard expansions involving optabs:

    CASE_FLT_FN (BUILT_IN_EXP):
    CASE_FLT_FN (BUILT_IN_EXP10):
    CASE_FLT_FN (BUILT_IN_POW10):
    CASE_FLT_FN (BUILT_IN_EXP2):
    CASE_FLT_FN (BUILT_IN_EXPM1):
    CASE_FLT_FN (BUILT_IN_LOGB):
    CASE_FLT_FN (BUILT_IN_LOG):
    CASE_FLT_FN (BUILT_IN_LOG10):
    CASE_FLT_FN (BUILT_IN_LOG2):
    CASE_FLT_FN (BUILT_IN_LOG1P):
    CASE_FLT_FN (BUILT_IN_TAN):
    CASE_FLT_FN (BUILT_IN_ASIN):
    CASE_FLT_FN (BUILT_IN_ACOS):
    CASE_FLT_FN (BUILT_IN_ATAN):
    CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
      /* Treat these like sqrt only if unsafe math optimizations are allowed,
         because of possible accuracy problems.  */
      if (! flag_unsafe_math_optimizations)
        break;
    [...]
    CASE_FLT_FN (BUILT_IN_ILOGB):
      if (! flag_unsafe_math_optimizations)
        break;
    [...]
    CASE_FLT_FN (BUILT_IN_ATAN2):
    CASE_FLT_FN (BUILT_IN_LDEXP):
    CASE_FLT_FN (BUILT_IN_SCALB):
    CASE_FLT_FN (BUILT_IN_SCALBN):
    CASE_FLT_FN (BUILT_IN_SCALBLN):
      if (! flag_unsafe_math_optimizations)
        break;
    [...]
    CASE_FLT_FN (BUILT_IN_SIN):
    CASE_FLT_FN (BUILT_IN_COS):
      if (! flag_unsafe_math_optimizations)
        break;
    [...]
    CASE_FLT_FN (BUILT_IN_SINCOS):
      if (! flag_unsafe_math_optimizations)
        break;

I think it's really up to the optab to decide whether it's safe
for !flag_unsafe_math_optimizations or not, and AFAICT, all optabs
but sh.md:sincossf3 already check.  This patch makes the sh pattern
check too.

Tested on sh-elf.  OK to install?

Thanks,
Richard


gcc/
        * config/sh/sh.md (sincossf3): Require flag_unsafe_math_optimizations.

diff --git a/gcc/config/sh/sh.md b/gcc/config/sh/sh.md
index 557a0f0..0c3b9f2 100644
--- a/gcc/config/sh/sh.md
+++ b/gcc/config/sh/sh.md
@@ -13722,7 +13722,7 @@ label:
        (unspec:SF [(match_operand:SF 2 "fp_arith_reg_operand")] UNSPEC_FCOSA))
    (set (match_operand:SF 1 "nonimmediate_operand")
        (unspec:SF [(match_dup 2)] UNSPEC_FSINA))]
-  "TARGET_FPU_ANY && TARGET_FSCA"
+  "TARGET_FPU_ANY && TARGET_FSCA && flag_unsafe_math_optimizations"
 {
   rtx scaled = gen_reg_rtx (SFmode);
   rtx truncated = gen_reg_rtx (SImode);