re PR tree-optimization/64910 (tree reassociation results in poor code)

	PR tree-optimization/64910
	* config/i386/i386.md (testqi_ext_3): Allow HImode.

	PR tree-optimization/64910
	* gcc.target/i386/bittest.c: New test.

From-SVN: r231871

gcc/ChangeLog

+2015-12-20  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/64910
+	* config/i386/i386.md (testqi_ext_3): Allow HImode.
+
 2015-12-20  Andrew Pinsi  <apinski@cavium.com>
 
 	* config/aarch64/atomics.md

gcc/config/i386/i386.md

@@ -7868,7 +7868,7 @@
 ;; Combine likes to form bit extractions for some tests.  Humor it.
 (define_insn "*testqi_ext_3"
   [(set (reg FLAGS_REG)
-	(compare (zero_extract:SWI48
+	(compare (zero_extract:SWI248
 		   (match_operand 0 "nonimmediate_operand" "rm")
 		   (match_operand 1 "const_int_operand" "n")
 		   (match_operand 2 "const_int_operand" "n"))

gcc/testsuite/ChangeLog

+2015-12-20  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/64910
+	* gcc.target/i386/bittest.c: New test.
+
 2015-12-20  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gnat.dg/complex1.adb: New test.

gcc/testsuite/gcc.target/i386/bittest.c

+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+extern int dbg_cnt (void);
+
+struct function
+{
+  unsigned int calls_setjmp:1;
+};
+extern struct function *cfun;
+unsigned char
+gate_rtl_cprop (void)
+{
+  return !(cfun + 0)->calls_setjmp && dbg_cnt ();
+}
+
+/* This should be implementable without performing a bitmask as we can
+   just use a test imm,mem.  So instructions which load the object from
+   memory and mask off bits are unnecessary.  In theory we can just count
+   the move-with-extension, and and testb instructions.  There should be
+   only one.  */
+/* { dg-final { scan-assembler-times "movzbl|and|testb" 1 { target { i?86-*-* x86_64-*-*} } } } */