Remove global call sets: loop-iv.c

Similar idea to the combine.c and gcse.c patches.

2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* loop-iv.c: Include regs.h and function-abi.h.
	(simplify_using_initial_values): Use insn_callee_abi to get the
	ABI of the call insn target.  Conservatively assume that
	partially-clobbered registers are altered.

From-SVN: r276326

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index c0454ce..1129ec5 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,12 @@
 2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>
 
+       * loop-iv.c: Include regs.h and function-abi.h.
+       (simplify_using_initial_values): Use insn_callee_abi to get the
+       ABI of the call insn target.  Conservatively assume that
+       partially-clobbered registers are altered.
+
+2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>
+
        * function-abi.h (call_clobbers_in_region): Declare.
        (call_clobbered_in_region_p): New function.
        * function-abi.cc (call_clobbers_in_region): Likewise.

diff --git a/gcc/loop-iv.c b/gcc/loop-iv.c
index 33be75a..d0e6994 100644 (file)
--- a/gcc/loop-iv.c
+++ b/gcc/loop-iv.c
@@ -62,6 +62,8 @@ along with GCC; see the file COPYING3.  If not see
 #include "dumpfile.h"
 #include "rtl-iter.h"
 #include "tree-ssa-loop-niter.h"
+#include "regs.h"
+#include "function-abi.h"
 
 /* Possible return values of iv_get_reaching_def.  */
 
@@ -1972,8 +1974,14 @@ simplify_using_initial_values (class loop *loop, enum rtx_code op, rtx *expr)
          CLEAR_REG_SET (this_altered);
          note_stores (insn, mark_altered, this_altered);
          if (CALL_P (insn))
-           /* Kill all call clobbered registers.  */
-           IOR_REG_SET_HRS (this_altered, regs_invalidated_by_call);
+           {
+             /* Kill all registers that might be clobbered by the call.
+                We don't track modes of hard registers, so we need to be
+                conservative and assume that partial kills are full kills.  */
+             function_abi callee_abi = insn_callee_abi (insn);
+             IOR_REG_SET_HRS (this_altered,
+                              callee_abi.full_and_partial_reg_clobbers ());
+           }
 
          if (suitable_set_for_replacement (insn, &dest, &src))
            {