[gcc r12-7390] arc: Fail conditional move expand patterns

[Claudiu Zissulescu]

https://gcc.gnu.org/g:d54cdd1538deebed97fb9531dc3e1a42eaf0a80f

commit r12-7390-gd54cdd1538deebed97fb9531dc3e1a42eaf0a80f
Author: Claudiu Zissulescu <claziss@synopsys.com>
Date:   Fri Feb 25 13:39:22 2022 +0200

    arc: Fail conditional move expand patterns
    
    If the movcc comparison is not valid it triggers an assert in the
    current implementation.  This behavior is not needed as we can FAIL
    the movcc expand pattern.
    
    gcc/
            * config/arc/arc.cc (gen_compare_reg): Return NULL_RTX if the
            comparison is not valid.
            * config/arc/arc.md (movsicc): Fail if comparison is not valid.
            (movdicc): Likewise.
            (movsfcc): Likewise.
            (movdfcc): Likewise.
    
    Signed-off-by: Claudiu Zissulescu <claziss@synopsys.com>

Diff:
---
 gcc/config/arc/arc.cc |  3 ++-
 gcc/config/arc/arc.md | 25 ++++++++++++++++++++-----
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/gcc/config/arc/arc.cc b/gcc/config/arc/arc.cc
index 8cc173519ab..c27ba99eb60 100644
--- a/gcc/config/arc/arc.cc
+++ b/gcc/config/arc/arc.cc
@@ -2256,7 +2256,8 @@ gen_compare_reg (rtx comparison, machine_mode omode)
   cmode = GET_MODE (x);
   if (cmode == VOIDmode)
     cmode = GET_MODE (y);
-  gcc_assert (cmode == SImode || cmode == SFmode || cmode == DFmode);
+  if (cmode != SImode && cmode != SFmode && cmode != DFmode)
+    return NULL_RTX;
   if (cmode == SImode)
     {
       if (!register_operand (x, SImode))
diff --git a/gcc/config/arc/arc.md b/gcc/config/arc/arc.md
index ace3cb70424..39b358052c1 100644
--- a/gcc/config/arc/arc.md
+++ b/gcc/config/arc/arc.md
@@ -1618,8 +1618,11 @@ core_3, archs4x, archs4xd, archs4xd_slow"
 		         (match_operand:SI 2 "nonmemory_operand" "")
  		         (match_operand:SI 3 "register_operand" "")))]
   ""
-  "operands[1] = gen_compare_reg (operands[1], VOIDmode);")
-
+  "
+  operands[1] = gen_compare_reg (operands[1], VOIDmode);
+  if (operands[1] == NULL_RTX)
+    FAIL;
+  ")
 
 (define_expand "movdicc"
   [(set (match_operand:DI 0 "dest_reg_operand" "")
@@ -1627,7 +1630,11 @@ core_3, archs4x, archs4xd, archs4xd_slow"
 		        (match_operand:DI 2 "nonmemory_operand" "")
 		        (match_operand:DI 3 "register_operand" "")))]
   ""
-  "operands[1] = gen_compare_reg (operands[1], VOIDmode);")
+  "
+  operands[1] = gen_compare_reg (operands[1], VOIDmode);
+  if (operands[1] == NULL_RTX)
+    FAIL;
+  ")
 
 
 (define_expand "movsfcc"
@@ -1636,7 +1643,11 @@ core_3, archs4x, archs4xd, archs4xd_slow"
 		      (match_operand:SF 2 "nonmemory_operand" "")
 		      (match_operand:SF 3 "register_operand" "")))]
   ""
-  "operands[1] = gen_compare_reg (operands[1], VOIDmode);")
+  "
+  operands[1] = gen_compare_reg (operands[1], VOIDmode);
+  if (operands[1] == NULL_RTX)
+    FAIL;
+  ")
 
 (define_expand "movdfcc"
   [(set (match_operand:DF 0 "dest_reg_operand" "")
@@ -1644,7 +1655,11 @@ core_3, archs4x, archs4xd, archs4xd_slow"
 		      (match_operand:DF 2 "nonmemory_operand" "")
 		      (match_operand:DF 3 "register_operand" "")))]
   ""
-  "operands[1] = gen_compare_reg (operands[1], VOIDmode);")
+  "
+  operands[1] = gen_compare_reg (operands[1], VOIDmode);
+  if (operands[1] == NULL_RTX)
+    FAIL;
+  ")
 
 (define_insn "*movsicc_insn"
   [(set (match_operand:SI 0 "dest_reg_operand" "=w,w")