re PR c/24414 (Old-style asms don't clobber memory)

gcc/
2016-06-06  Bernd Edlinger  <bernd.edlinger@hotmail.de>

        PR c/24414
        * cfgexpand.c (expand_asm_loc): Remove handling for ADDR_EXPR.
        Implicitly clobber memory for basic asm with non-empty assembler
        string.  Use targetm.md_asm_adjust also here.
        * compare-elim.c (arithmetic_flags_clobber_p): Use asm_noperands here.
        * final.c (final_scan_insn): Handle basic asm in PARALLEL block.
        * gimple.c (gimple_asm_clobbers_memory_p): Handle basic asm with
        non-empty assembler string.
        * ira.c (compute_regs_asm_clobbered): Use asm_noperands here.
        * recog.c (asm_noperands): Handle basic asm in PARALLEL block.
        (decode_asm_operands): Handle basic asm in PARALLEL block.
        (extract_insn): Handle basic asm in PARALLEL block.
        * doc/extend.texi: Mention new behavior of basic asm.
        * config/ia64/ia64 (rtx_needs_barrier): Handle ASM_INPUT here.
        * config/pa/pa.c (branch_to_delay_slot_p, branch_needs_nop_p,
        branch_needs_nop_p): Use asm_noperands.

gcc/testsuite/
2016-06-06  Bernd Edlinger  <bernd.edlinger@hotmail.de>

        PR c/24414
        * gcc.target/i386/pr24414.c: New test.

From-SVN: r237133

1 files changed, 27 insertions, 5 deletions

diff --git a/gcc/recog.c b/gcc/recog.c
index 92b2aa3..80d1779 100644
--- a/gcc/recog.c
+++ b/gcc/recog.c
@@ -1470,22 +1470,34 @@ extract_asm_operands (rtx body)
 
 /* If BODY is an insn body that uses ASM_OPERANDS,
    return the number of operands (both input and output) in the insn.
+   If BODY is an insn body that uses ASM_INPUT with CLOBBERS in PARALLEL,
+   return 0.
    Otherwise return -1.  */
 
 int
 asm_noperands (const_rtx body)
 {
   rtx asm_op = extract_asm_operands (CONST_CAST_RTX (body));
-  int n_sets = 0;
+  int i, n_sets = 0;
 
   if (asm_op == NULL)
-    return -1;
+    {
+      if (GET_CODE (body) == PARALLEL && XVECLEN (body, 0) >= 2
+	  && GET_CODE (XVECEXP (body, 0, 0)) == ASM_INPUT)
+	{
+	  /* body is [(asm_input ...) (clobber (reg ...))...].  */
+	  for (i = XVECLEN (body, 0) - 1; i > 0; i--)
+	    if (GET_CODE (XVECEXP (body, 0, i)) != CLOBBER)
+	      return -1;
+	  return 0;
+	}
+      return -1;
+    }
 
   if (GET_CODE (body) == SET)
     n_sets = 1;
   else if (GET_CODE (body) == PARALLEL)
     {
-      int i;
       if (GET_CODE (XVECEXP (body, 0, 0)) == SET)
 	{
 	  /* Multiple output operands, or 1 output plus some clobbers:
@@ -1540,9 +1552,12 @@ asm_noperands (const_rtx body)
    the locations of the operands within the insn into the vector OPERAND_LOCS,
    and the constraints for the operands into CONSTRAINTS.
    Write the modes of the operands into MODES.
+   Write the location info into LOC.
    Return the assembler-template.
+   If BODY is an insn body that uses ASM_INPUT with CLOBBERS in PARALLEL,
+   return the basic assembly string.
 
-   If MODES, OPERAND_LOCS, CONSTRAINTS or OPERANDS is 0,
+   If LOC, MODES, OPERAND_LOCS, CONSTRAINTS or OPERANDS is 0,
    we don't store that info.  */
 
 const char *
@@ -1603,6 +1618,12 @@ decode_asm_operands (rtx body, rtx *operands, rtx **operand_locs,
 	      }
 	    nbase = i;
 	  }
+	else if (GET_CODE (asmop) == ASM_INPUT)
+	  {
+	    if (loc)
+	      *loc = ASM_INPUT_SOURCE_LOCATION (asmop);
+	    return XSTR (asmop, 0);
+	  }
 	break;
       }
 
@@ -2245,7 +2266,8 @@ extract_insn (rtx_insn *insn)
     case PARALLEL:
       if ((GET_CODE (XVECEXP (body, 0, 0)) == SET
 	   && GET_CODE (SET_SRC (XVECEXP (body, 0, 0))) == ASM_OPERANDS)
-	  || GET_CODE (XVECEXP (body, 0, 0)) == ASM_OPERANDS)
+	  || GET_CODE (XVECEXP (body, 0, 0)) == ASM_OPERANDS
+	  || GET_CODE (XVECEXP (body, 0, 0)) == ASM_INPUT)
 	goto asm_insn;
       else
 	goto normal_insn;