diff --git a/gcc/combine.cc b/gcc/combine.cc
index 0d99fa541c5..e46d202d0a7 100644
--- a/gcc/combine.cc
+++ b/gcc/combine.cc
@@ -11998,11 +11998,15 @@ simplify_compare_const (enum rtx_code code, machine_mode mode,
      x0 >= 0x40.  */
   if ((code == LEU || code == LTU || code == GEU || code == GTU)
       && is_a <scalar_int_mode> (GET_MODE (op0), &int_mode)
+      && HWI_COMPUTABLE_MODE_P (int_mode)
       && MEM_P (op0)
       && !MEM_VOLATILE_P (op0)
       /* The optimization makes only sense for constants which are big enough
 	 so that we have a chance to chop off something at all.  */
       && (unsigned HOST_WIDE_INT) const_op > 0xff
+      /* Bail out, if the constant does not fit into INT_MODE.  */
+      && (unsigned HOST_WIDE_INT) const_op
+	 < ((HOST_WIDE_INT_1U << (GET_MODE_PRECISION (int_mode) - 1) << 1) - 1)
       /* Ensure that we do not overflow during normalization.  */
       && (code != GTU || (unsigned HOST_WIDE_INT) const_op < HOST_WIDE_INT_M1U))
     {
diff --git a/gcc/testsuite/gcc.dg/cmp-mem-const-1.c b/gcc/testsuite/gcc.dg/cmp-mem-const-1.c
index 263ad98af79..4f21a1ade4a 100644
--- a/gcc/testsuite/gcc.dg/cmp-mem-const-1.c
+++ b/gcc/testsuite/gcc.dg/cmp-mem-const-1.c
@@ -1,6 +1,6 @@
 /* { dg-do compile { target { lp64 } } } */
 /* { dg-options "-O1 -fdump-rtl-combine-details" } */
-/* { dg-final { scan-rtl-dump "narrow comparison from mode DI to QI" "combine" } } */
+/* { dg-final { scan-rtl-dump "narrow comparison from mode .I to QI" "combine" } } */
 
 typedef __UINT64_TYPE__ uint64_t;
 
diff --git a/gcc/testsuite/gcc.dg/cmp-mem-const-2.c b/gcc/testsuite/gcc.dg/cmp-mem-const-2.c
index a7cc5348295..7b722951594 100644
--- a/gcc/testsuite/gcc.dg/cmp-mem-const-2.c
+++ b/gcc/testsuite/gcc.dg/cmp-mem-const-2.c
@@ -1,6 +1,6 @@
 /* { dg-do compile { target { lp64 } } } */
 /* { dg-options "-O1 -fdump-rtl-combine-details" } */
-/* { dg-final { scan-rtl-dump "narrow comparison from mode DI to QI" "combine" } } */
+/* { dg-final { scan-rtl-dump "narrow comparison from mode .I to QI" "combine" } } */
 
 typedef __UINT64_TYPE__ uint64_t;
 
diff --git a/gcc/testsuite/gcc.dg/cmp-mem-const-3.c b/gcc/testsuite/gcc.dg/cmp-mem-const-3.c
index 06f80bf72d8..ed5059d3807 100644
--- a/gcc/testsuite/gcc.dg/cmp-mem-const-3.c
+++ b/gcc/testsuite/gcc.dg/cmp-mem-const-3.c
@@ -1,6 +1,6 @@
 /* { dg-do compile { target { lp64 } } } */
 /* { dg-options "-O1 -fdump-rtl-combine-details" } */
-/* { dg-final { scan-rtl-dump "narrow comparison from mode DI to HI" "combine" } } */
+/* { dg-final { scan-rtl-dump "narrow comparison from mode .I to HI" "combine" } } */
 
 typedef __UINT64_TYPE__ uint64_t;
 
diff --git a/gcc/testsuite/gcc.dg/cmp-mem-const-4.c b/gcc/testsuite/gcc.dg/cmp-mem-const-4.c
index 407999abf7e..23e83372bee 100644
--- a/gcc/testsuite/gcc.dg/cmp-mem-const-4.c
+++ b/gcc/testsuite/gcc.dg/cmp-mem-const-4.c
@@ -1,6 +1,6 @@
 /* { dg-do compile { target { lp64 } } } */
 /* { dg-options "-O1 -fdump-rtl-combine-details" } */
-/* { dg-final { scan-rtl-dump "narrow comparison from mode DI to HI" "combine" } } */
+/* { dg-final { scan-rtl-dump "narrow comparison from mode .I to HI" "combine" } } */
 
 typedef __UINT64_TYPE__ uint64_t;
 
diff --git a/gcc/testsuite/gcc.dg/cmp-mem-const-5.c b/gcc/testsuite/gcc.dg/cmp-mem-const-5.c
index e16773f5bcf..d266896a25e 100644
--- a/gcc/testsuite/gcc.dg/cmp-mem-const-5.c
+++ b/gcc/testsuite/gcc.dg/cmp-mem-const-5.c
@@ -1,6 +1,6 @@
-/* { dg-do compile { target { lp64 } } } */
+/* { dg-do compile { target { lp64 } && ! target { sparc*-*-* } } } */
 /* { dg-options "-O1 -fdump-rtl-combine-details" } */
-/* { dg-final { scan-rtl-dump "narrow comparison from mode DI to SI" "combine" } } */
+/* { dg-final { scan-rtl-dump "narrow comparison from mode .I to SI" "combine" } } */
 
 typedef __UINT64_TYPE__ uint64_t;
 
diff --git a/gcc/testsuite/gcc.dg/cmp-mem-const-6.c b/gcc/testsuite/gcc.dg/cmp-mem-const-6.c
index 8f53b5678bd..68d7a9d0265 100644
--- a/gcc/testsuite/gcc.dg/cmp-mem-const-6.c
+++ b/gcc/testsuite/gcc.dg/cmp-mem-const-6.c
@@ -1,6 +1,6 @@
-/* { dg-do compile { target { lp64 } } } */
+/* { dg-do compile { target { lp64 } && ! target { sparc*-*-* } } } */
 /* { dg-options "-O1 -fdump-rtl-combine-details" } */
-/* { dg-final { scan-rtl-dump "narrow comparison from mode DI to SI" "combine" } } */
+/* { dg-final { scan-rtl-dump "narrow comparison from mode .I to SI" "combine" } } */
 
 typedef __UINT64_TYPE__ uint64_t;