[gcc r12-3655] Fix ICE in pass_rpad.

[gcc r12-3655] Fix ICE in pass_rpad.

[hongtao Liu]

https://gcc.gnu.org/g:e666a0a22a5c11b5bb894a75b73b6b7f3e364e4d

commit r12-3655-ge666a0a22a5c11b5bb894a75b73b6b7f3e364e4d
Author: liuhongt <hongtao.liu@intel.com>
Date:   Sat Sep 18 10:49:54 2021 +0800

    Fix ICE in pass_rpad.
    
    Besides conversion instructions, pass_rpad also handles scalar
    sqrt/rsqrt/rcp/round instructions, while r12-3614 should only want to
    handle conversion instructions, so fix it.
    
    gcc/ChangeLog:
    
            * config/i386/i386-features.c (remove_partial_avx_dependency):
            Restrict TARGET_USE_VECTOR_FP_CONVERTS and
            TARGET_USE_VECTOR_CONVERTS to conversion instructions only.

Diff:
---
 gcc/config/i386/i386-features.c | 27 ++++++++++++++++++++++-----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/gcc/config/i386/i386-features.c b/gcc/config/i386/i386-features.c
index a525a83afd3..14f816feee0 100644
--- a/gcc/config/i386/i386-features.c
+++ b/gcc/config/i386/i386-features.c
@@ -2165,7 +2165,7 @@ make_pass_insert_endbr_and_patchable_area (gcc::context *ctxt)
 }
 
 /* At entry of the nearest common dominator for basic blocks with
-   conversions, generate a single
+   conversions/rcp/sqrt/rsqrt/round, generate a single
 	vxorps %xmmN, %xmmN, %xmmN
    for all
 	vcvtss2sd  op, %xmmN, %xmmX
@@ -2211,13 +2211,27 @@ remove_partial_avx_dependency (void)
 	    continue;
 
 	  /* Convert PARTIAL_XMM_UPDATE_TRUE insns, DF -> SF, SF -> DF,
-	     SI -> SF, SI -> DF, DI -> SF, DI -> DF, to vec_dup and
-	     vec_merge with subreg.  */
+	     SI -> SF, SI -> DF, DI -> SF, DI -> DF, sqrt, rsqrt, rcp,
+	     round, to vec_dup and vec_merge with subreg.  */
 	  rtx src = SET_SRC (set);
 	  rtx dest = SET_DEST (set);
 	  machine_mode dest_mode = GET_MODE (dest);
-	  machine_mode src_mode = GET_MODE (XEXP (src, 0));
+	  bool convert_p = false;
+	  switch (GET_CODE (src))
+	    {
+	    case FLOAT:
+	    case FLOAT_EXTEND:
+	    case FLOAT_TRUNCATE:
+	    case UNSIGNED_FLOAT:
+	      convert_p = true;
+	      break;
+	    default:
+	      break;
+	    }
 
+	  /* Only hanlde conversion here.  */
+	  machine_mode src_mode
+	    = convert_p ? GET_MODE (XEXP (src, 0)) : VOIDmode;
 	  switch (src_mode)
 	    {
 	    case E_SFmode:
@@ -2232,8 +2246,11 @@ remove_partial_avx_dependency (void)
 		  || !TARGET_SSE_PARTIAL_REG_CONVERTS_DEPENDENCY)
 		continue;
 	      break;
-	    default:
+	    case E_VOIDmode:
+	      gcc_assert (!convert_p);
 	      break;
+	    default:
+	      gcc_unreachable ();
 	    }
 
 	  if (!v4sf_const0)