diff mbox series

c-family: Fix up shorten_compare for decimal vs. non-decimal float comparison [PR104510]

Message ID 20220215100743.GM2646553@tucnak
State New
Headers show
Series c-family: Fix up shorten_compare for decimal vs. non-decimal float comparison [PR104510] | expand

Commit Message

Jakub Jelinek Feb. 15, 2022, 10:07 a.m. UTC 
Hi!

The comment in shorten_compare says:
  /* If either arg is decimal float and the other is float, fail.  */
but the callers of shorten_compare don't expect anything like failure
as a possibility from the function, callers require that the function
promotes the operands to the same type, whether the original selected
*restype_ptr one or some shortened.
So, if we choose not to shorten, we should still promote to the original
*restype_ptr.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2022-02-15  Jakub Jelinek  <jakub@redhat.com>

	PR c/104510
	* c-common.cc (shorten_compare): Convert original arguments to
	the original *restype_ptr when mixing binary and decimal float.

	* gcc.dg/dfp/pr104510.c: New test.


	Jakub

Comments

Jason Merrill Feb. 15, 2022, 11:45 p.m. UTC | #1 
On 2/15/22 05:07, Jakub Jelinek wrote:
> Hi!
> 
> The comment in shorten_compare says:
>    /* If either arg is decimal float and the other is float, fail.  */
> but the callers of shorten_compare don't expect anything like failure
> as a possibility from the function, callers require that the function
> promotes the operands to the same type, whether the original selected
> *restype_ptr one or some shortened.
> So, if we choose not to shorten, we should still promote to the original
> *restype_ptr.
> 
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

OK.

> 2022-02-15  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR c/104510
> 	* c-common.cc (shorten_compare): Convert original arguments to
> 	the original *restype_ptr when mixing binary and decimal float.
> 
> 	* gcc.dg/dfp/pr104510.c: New test.
> 
> --- gcc/c-family/c-common.cc.jj	2022-02-04 14:36:53.998619364 +0100
> +++ gcc/c-family/c-common.cc	2022-02-14 19:07:14.305068950 +0100
> @@ -3174,7 +3174,11 @@ shorten_compare (location_t loc, tree *o
>     else if (real1 && real2
>   	   && (DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop0)))
>   	       || DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop1)))))
> -    return NULL_TREE;
> +    {
> +      type = *restype_ptr;
> +      primop0 = op0;
> +      primop1 = op1;
> +    }
>   
>     else if (real1 && real2
>   	   && (TYPE_PRECISION (TREE_TYPE (primop0))
> --- gcc/testsuite/gcc.dg/dfp/pr104510.c.jj	2022-02-14 19:11:05.610860035 +0100
> +++ gcc/testsuite/gcc.dg/dfp/pr104510.c	2022-02-14 19:10:42.819176224 +0100
> @@ -0,0 +1,12 @@
> +/* PR c/104510 */
> +/* { dg-do compile } */
> +/* { dg-options "" } */
> +
> +float f;
> +_Decimal64 d;
> +
> +int
> +foo (void)
> +{
> +  return d > (_Decimal32) (_Decimal64) f;
> +}
> 
> 	Jakub
>
diff mbox series

Patch

--- gcc/c-family/c-common.cc.jj	2022-02-04 14:36:53.998619364 +0100
+++ gcc/c-family/c-common.cc	2022-02-14 19:07:14.305068950 +0100
@@ -3174,7 +3174,11 @@  shorten_compare (location_t loc, tree *o
   else if (real1 && real2
 	   && (DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop0)))
 	       || DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop1)))))
-    return NULL_TREE;
+    {
+      type = *restype_ptr;
+      primop0 = op0;
+      primop1 = op1;
+    }
 
   else if (real1 && real2
 	   && (TYPE_PRECISION (TREE_TYPE (primop0))
--- gcc/testsuite/gcc.dg/dfp/pr104510.c.jj	2022-02-14 19:11:05.610860035 +0100
+++ gcc/testsuite/gcc.dg/dfp/pr104510.c	2022-02-14 19:10:42.819176224 +0100
@@ -0,0 +1,12 @@ 
+/* PR c/104510 */
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+float f;
+_Decimal64 d;
+
+int
+foo (void)
+{
+  return d > (_Decimal32) (_Decimal64) f;
+}