Replace the once vacuously true, and now vacuously false, test for
existence of a conditional move instruction for a given mode, with one
that actually checks what it's supposed to. Add a test case so we don't
miss such things in future.
The test is powerpc-specific. It would be good to have an i386 version
of the test as well, if someone can help with that.
Bootstrapped and tested on powerpc64-unknown-linux-gnu with no new
regressions. Ok for trunk?
Thanks,
Bill
gcc:
2012-08-13 Bill Schmidt <wschm...@linux.vnet.ibm.com>
PR tree-optimization/54240
* tree-ssa-phiopt.c (hoist_adjacent_loads): Correct test for
existence of conditional move with given mode.
gcc/testsuite:
2012-08-13 Bill Schmidt <wschm...@linux.vnet.ibm.com>
PR tree-optimization/54240
* gcc.target/powerpc/pr54240.c: New test.
Index: gcc/testsuite/gcc.target/powerpc/pr54240.c
===================================================================
--- gcc/testsuite/gcc.target/powerpc/pr54240.c (revision 0)
+++ gcc/testsuite/gcc.target/powerpc/pr54240.c (revision 0)
@@ -0,0 +1,27 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -misel -fdump-tree-phiopt-details" } */
+
+typedef struct s {
+ int v;
+ int b;
+ struct s *l;
+ struct s *r;
+} S;
+
+
+int foo(S *s)
+{
+ S *this;
+ S *next;
+
+ this = s;
+ if (this->b)
+ next = this->l;
+ else
+ next = this->r;
+
+ return next->v;
+}
+
+/* { dg-final { scan-tree-dump "Hoisting adjacent loads" "phiopt1" } } */
+/* { dg-final { cleanup-tree-dump "phiopt1" } } */
Index: gcc/tree-ssa-phiopt.c
===================================================================
--- gcc/tree-ssa-phiopt.c (revision 190305)
+++ gcc/tree-ssa-phiopt.c (working copy)
@@ -1843,7 +1843,8 @@ hoist_adjacent_loads (basic_block bb0, basic_block
/* Check the mode of the arguments to be sure a conditional move
can be generated for it. */
- if (!optab_handler (cmov_optab, TYPE_MODE (TREE_TYPE (arg1))))
+ if (optab_handler (movcc_optab, TYPE_MODE (TREE_TYPE (arg1)))
+ == CODE_FOR_nothing)
continue;
/* Both statements must be assignments whose RHS is a COMPONENT_REF. */
