[PATCH v2] sh: libgcc: Implement fenv rouding and exceptions for soft-fp [PR118257]

Implement fenv rouding and exceptions for soft-fp, as per SuperH
arch specification.

No new tests required, as it's already covered by many torture tests
with fenv_exceptions.

	PR target/118257

libgcc/ChangeLog:

	* config/sh/sfp-machine.h (_FPU_GETCW): Implement with builtin.
	(_FPU_SETCW): Likewise.
	(FP_EX_ENABLE_SHIFT): Derive from arch spec.
	(FP_EX_CAUSE_SHIFT): Likewise.
	(FP_RND_MASK): Likewise.
	(FP_EX_INVALID): Likewise.
	(FP_EX_DIVZERO): Likewise.
	(FP_EX_ALL): Likewise.
	(FP_EX_OVERFLOW): Likewise.
	(FP_EX_UNDERFLOW): Likewise.
	(FP_EX_INEXACT): Likewise.
	(_FP_DECL_EX): Declear default FCSR value.
	(FP_RND_NEAREST): Derive from arch spec.
	(FP_RND_ZERO): Likewise.
	(FP_INIT_ROUNDMODE): Likewise.
	(FP_ROUNDMODE): Likewise.
	(FP_TRAPPING_EXCEPTIONS): Likewise.
	(FP_HANDLE_EXCEPTIONS): Implement with _FPU_SETCW.

diff --git a/libgcc/config/sh/sfp-machine.h b/libgcc/config/sh/sfp-machine.h
index 67bc41516a38e94490c9ba63aece9cf8f17a1a02..8030c802154e1b6f2c99479a8ceb00350baba584 100644 (file)
--- a/libgcc/config/sh/sfp-machine.h
+++ b/libgcc/config/sh/sfp-machine.h
@@ -76,6 +76,52 @@ typedef int __gcc_CMPtype __attribute__ ((mode (__libgcc_cmp_return__)));
     R##_c = FP_CLS_NAN;                                                \
   } while (0)
 
+#ifdef __SH_FPU_ANY__
+#define _FPU_GETCW(fpscr) fpscr = __builtin_sh_get_fpscr ()
+#define _FPU_SETCW(fpscr) __builtin_sh_set_fpscr (fpscr)
+#define FP_EX_ENABLE_SHIFT 5
+#define FP_EX_CAUSE_SHIFT      10
+
+#define        FP_EX_INVALID   0x0040
+#define        FP_EX_DIVZERO   0x0020
+#if defined (__SH2E__)
+#define        FP_EX_ALL       (FP_EX_DIVZERO | FP_EX_INVALID)
+#else
+#define        FP_EX_OVERFLOW  0x0010
+#define        FP_EX_UNDERFLOW 0x0008
+#define        FP_EX_INEXACT   0x0004
+#define        FP_EX_ALL       (FP_EX_DIVZERO | FP_EX_INEXACT | \
+    FP_EX_INVALID | FP_EX_OVERFLOW | FP_EX_UNDERFLOW)
+#endif
+#define _FP_DECL_EX \
+  unsigned int _fcsr __attribute__ ((unused)) = FP_RND_NEAREST
+/* Rounding modes.  */
+#define        FP_RND_NEAREST  0x0
+#define        FP_RND_ZERO     0x1
+/* Placeholder, hardware does not have PINF/MINF modes.  */
+#define FP_RND_PINF     0x2
+#define FP_RND_MINF     0x3
+#define FP_RND_MASK     3
+
+#define FP_INIT_ROUNDMODE _FPU_GETCW (_fcsr)
+#define FP_ROUNDMODE (_fcsr & FP_RND_MASK)
+#define FP_TRAPPING_EXCEPTIONS ((_fcsr >> FP_EX_ENABLE_SHIFT) & FP_EX_ALL)
+#define FP_HANDLE_EXCEPTIONS                           \
+  do {                                                 \
+    _fcsr &= ~(FP_EX_ALL << FP_EX_CAUSE_SHIFT);                \
+    _fcsr |= _fex | (_fex << FP_EX_CAUSE_SHIFT);       \
+    _FPU_SETCW (_fcsr);                        \
+  } while (0)
+#else
+#define FP_EX_INVALID (1 << 4)
+#define FP_EX_DIVZERO (1 << 3)
+#if !defined (__SH2E__)
+#define FP_EX_OVERFLOW (1 << 2)
+#define FP_EX_UNDERFLOW (1 << 1)
+#define FP_EX_INEXACT (1 << 0)
+#endif
+#endif
+
 #define _FP_TININESS_AFTER_ROUNDING 1
 
 #define __LITTLE_ENDIAN 1234