RE: [Patch] Fix for MIPS PR target/65604

[Steve Ellcey]

On Tue, 2015-12-15 at 15:13 +0000, Moore, Catherine wrote:

> 
> HI Steve, The patch is OK.  Will you please add a test case and repost?
> Thanks,
> Catherine

Here is the patch with a test case.

2015-12-15  Steve Ellcey  <sell...@imgtec.com>

        PR target/65604
        * config/mips/mips.c (mips_output_division): Check flag_delayed_branch.


diff --git a/gcc/config/mips/mips.c b/gcc/config/mips/mips.c
index 6145944..8444a91 100644
--- a/gcc/config/mips/mips.c
+++ b/gcc/config/mips/mips.c
@@ -13687,9 +13687,17 @@ mips_output_division (const char *division, rtx 
*operands)
        }
       else
        {
-         output_asm_insn ("%(bne\t%2,%.,1f", operands);
-         output_asm_insn (s, operands);
-         s = "break\t7%)\n1:";
+         if (flag_delayed_branch)
+           {
+             output_asm_insn ("%(bne\t%2,%.,1f", operands);
+             output_asm_insn (s, operands);
+             s = "break\t7%)\n1:";
+           }
+         else
+           {
+             output_asm_insn (s, operands);
+             s = "bne\t%2,%.,1f\n\tnop\n\tbreak\t7\n1:";
+           }
        }
     }
   return s;



2015-12-15  Steve Ellcey  <sell...@imgtec.com>

        PR target/65604
        * gcc.target/mips/div-delay.c: New test.


diff --git a/gcc/testsuite/gcc.target/mips/div-delay.c 
b/gcc/testsuite/gcc.target/mips/div-delay.c
index e69de29..bdeb125 100644
--- a/gcc/testsuite/gcc.target/mips/div-delay.c
+++ b/gcc/testsuite/gcc.target/mips/div-delay.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-march=mips1 -fno-delayed-branch" } */
+/* { dg-final { scan-assembler "\tbne\t.*\tnop" } } */
+
+/* Ensure that mips1 does not put anything in the delay slot of the bne
+   instruction when checking for divide by zero.  mips2+ systems use teq
+   instead of bne and teq has no delay slot.  */
+
+NOCOMPRESSION int
+foo (int a, int b)
+{
+  return a / b;
+}