This patch fixes some test cases for PowerPC.
The tests pr39902-2.c, dfp-dd.c, and dfp-td.c reports as errors
when gcc is configured without dfp support. This patch will make the
tests to be reported as unsupported.
The test and-1.c has wrong logic.
In the formula:
y & ~(y & -y)
The part (y & -y) is always a mask with one bit set, which corresponds
to the least significant "1" bit in y.
The final result is that bit, is set to zero (y & ~mask)
There is no boolean simplification possible, and the compiler always
produces
a nand instruction.
The test should be:
y & ~(y & ~x)
Which can be simplified to:
y & (~y or x)
y.~y or yx
yx
Optimized code has a single "and" instruction. Sub-optimal optimization
will generate a "nand" or an "orc" / "and" pair (as in gcc-4.3).
I also would like to request for someone to commit the patch after
approval, as I have no WAA privileges.
Regards,
Edmar
2011-04-19 Edmar Wienskoski ed...@freescale.com
* gcc.target/powerpc/pr39902-2.c: Skip testcase for non-dfp
targets.
* gcc.target/powerpc/dfp-dd.c: ditto
* gcc.target/powerpc/dfp-td.c: ditto
* gcc.target/powerpc/and-1.c: Fixed testcase logic
Index: gcc-20100630/gcc/testsuite/gcc.target/powerpc/pr39902-2.c
===================================================================
--- gcc-20100630/gcc/testsuite/gcc.target/powerpc/pr39902-2.c (revision 161589)
+++ gcc-20100630/gcc/testsuite/gcc.target/powerpc/pr39902-2.c (working copy)
@@ -1,7 +1,7 @@
/* Check that simplification "x*(-1)" -> "-x" is not performed for decimal
float types. */
-/* { dg-do compile { target { powerpc*-*-linux* && powerpc_fprs } } } */
+/* { dg-do compile { target { powerpc*-*-linux* && { powerpc_fprs && dfp } } } } */
/* { dg-options "-std=gnu99 -O -mcpu=power6" } */
/* { dg-final { scan-assembler-not "fneg" } } */
Index: gcc-20100630/gcc/testsuite/gcc.target/powerpc/dfp-dd.c
===================================================================
--- gcc-20100630/gcc/testsuite/gcc.target/powerpc/dfp-dd.c (revision 161589)
+++ gcc-20100630/gcc/testsuite/gcc.target/powerpc/dfp-dd.c (working copy)
@@ -1,6 +1,6 @@
/* Test generation of DFP instructions for POWER6. */
/* Origin: Janis Johnson <janis...@us.ibm.com> */
-/* { dg-do compile { target { powerpc*-*-linux* && powerpc_fprs } } } */
+/* { dg-do compile { target { powerpc*-*-linux* && { powerpc_fprs && dfp } } } } */
/* { dg-options "-std=gnu99 -mcpu=power6" } */
/* { dg-final { scan-assembler "dadd" } } */
Index: gcc-20100630/gcc/testsuite/gcc.target/powerpc/dfp-td.c
===================================================================
--- gcc-20100630/gcc/testsuite/gcc.target/powerpc/dfp-td.c (revision 161589)
+++ gcc-20100630/gcc/testsuite/gcc.target/powerpc/dfp-td.c (working copy)
@@ -1,6 +1,6 @@
/* Test generation of DFP instructions for POWER6. */
/* Origin: Janis Johnson <janis...@us.ibm.com> */
-/* { dg-do compile { target { powerpc*-*-linux* && powerpc_fprs } } } */
+/* { dg-do compile { target { powerpc*-*-linux* && { powerpc_fprs && dfp } } } } */
/* { dg-options "-std=gnu99 -mcpu=power6" } */
/* { dg-final { scan-assembler "daddq" } } */
Index: gcc-20100630/gcc/testsuite/gcc.dg/and-1.c
===================================================================
--- gcc-20100630/gcc/testsuite/gcc.dg/and-1.c (revision 161589)
+++ gcc-20100630/gcc/testsuite/gcc.dg/and-1.c (working copy)
@@ -3,8 +3,9 @@
/* { dg-final { scan-assembler "and" { target powerpc*-*-* spu-*-* } } } */
/* There should be no nand for this testcase (for either PPC or SPU). */
/* { dg-final { scan-assembler-not "nand" { target powerpc*-*-* spu-*-* } } } */
+/* { dg-final { scan-assembler-not "orc" { target powerpc*-*-* spu-*-* } } } */
-int f(int y)
+int f(int y, int x)
{
- return y & ~(y & -y);
+ return y & ~(y & ~x);
}
