[PATCH, i386]: Fix PR target/39482

[Uros Bizjak <ubizjak at gmail dot com>]

Hello!

According to the comment above inline_secondary_memory_needed:

<quote>
  The macro can't work reliably when one of the CLASSES is class containing
  registers from multiple units (SSE, MMX, integer).  We avoid this by 
never
  combining those units in single alternative in the machine description.
  Ensure that this constraint holds to avoid unexpected surprises.
</quote>

Several constraints in the insn patterns still violate this requirement.

Attached patch fixes this oversight.

2009-03-17  Uros Bizjak  <ubizjak@gmail.com>

   PR target/39482
   * config/i386/i386.md (*truncdfsf_mixed): Avoid combining registers
   from different units in a single alternative.
   (*truncdfsf_i387): Ditto.
   (*truncxfsf2_mixed): Ditto.
   (*truncxfdf2_mixed): Ditto.

testsuite/ChangeLog:

   PR target/39482
   * gcc.target/i386/pr39482.c: New test.

Patch was bootstrapped and regression tested on x86_64-pc-linux-gnu 
{,-m32}. Patch is committed to mainline SVN and will be committed to 
gcc-4.3 branch after some days.

Uros.
Index: config/i386/i386.md
===================================================================
--- config/i386/i386.md	(revision 144907)
+++ config/i386/i386.md	(working copy)
@@ -4458,35 +4458,33 @@
    (set_attr "mode" "SF")])
 
 (define_insn "*truncdfsf_mixed"
-  [(set (match_operand:SF 0 "nonimmediate_operand"   "=m,?fx*r,Y2")
+  [(set (match_operand:SF 0 "nonimmediate_operand"   "=m,Y2 ,?f,?x,?*r")
 	(float_truncate:SF
-	  (match_operand:DF 1 "nonimmediate_operand" "f ,f    ,Y2m")))
-   (clobber (match_operand:SF 2 "memory_operand"     "=X,m    ,X"))]
+	  (match_operand:DF 1 "nonimmediate_operand" "f ,Y2m,f ,f ,f")))
+   (clobber (match_operand:SF 2 "memory_operand"     "=X,X  ,m ,m ,m"))]
   "TARGET_MIX_SSE_I387"
 {
   switch (which_alternative)
     {
     case 0:
       return output_387_reg_move (insn, operands);
-
     case 1:
-      return "#";
-    case 2:
       return "%vcvtsd2ss\t{%1, %d0|%d0, %1}";
+
     default:
-      gcc_unreachable ();
+      return "#";
     }
 }
-  [(set_attr "type" "fmov,multi,ssecvt")
-   (set_attr "unit" "*,i387,*")
-   (set_attr "prefix" "orig,orig,maybe_vex")
+  [(set_attr "type" "fmov,ssecvt,multi,multi,multi")
+   (set_attr "unit" "*,*,i387,i387,i387")
+   (set_attr "prefix" "orig,maybe_vex,orig,orig,orig")
    (set_attr "mode" "SF")])
 
 (define_insn "*truncdfsf_i387"
-  [(set (match_operand:SF 0 "nonimmediate_operand" "=m,?fx*r")
+  [(set (match_operand:SF 0 "nonimmediate_operand"   "=m,?f,?x,?*r")
 	(float_truncate:SF
-	  (match_operand:DF 1 "nonimmediate_operand" "f,f")))
-   (clobber (match_operand:SF 2 "memory_operand" "=X,m"))]
+	  (match_operand:DF 1 "nonimmediate_operand" "f ,f ,f ,f")))
+   (clobber (match_operand:SF 2 "memory_operand"     "=X,m ,m ,m"))]
   "TARGET_80387"
 {
   switch (which_alternative)
@@ -4494,14 +4492,12 @@
     case 0:
       return output_387_reg_move (insn, operands);
 
-    case 1:
-      return "#";
     default:
-      gcc_unreachable ();
+      return "#";
     }
 }
-  [(set_attr "type" "fmov,multi")
-   (set_attr "unit" "*,i387")
+  [(set_attr "type" "fmov,multi,multi,multi")
+   (set_attr "unit" "*,i387,i387,i387")
    (set_attr "mode" "SF")])
 
 (define_insn "*truncdfsf2_i387_1"
@@ -4552,31 +4548,31 @@
 })
 
 (define_insn "*truncxfsf2_mixed"
-  [(set (match_operand:SF 0 "nonimmediate_operand" "=m,?fx*r")
+  [(set (match_operand:SF 0 "nonimmediate_operand" "=m,?f,?x,?*r")
 	(float_truncate:SF
-	  (match_operand:XF 1 "register_operand" "f,f")))
-   (clobber (match_operand:SF 2 "memory_operand" "=X,m"))]
+	  (match_operand:XF 1 "register_operand"   "f ,f ,f ,f")))
+   (clobber (match_operand:SF 2 "memory_operand"   "=X,m ,m ,m"))]
   "TARGET_80387"
 {
   gcc_assert (!which_alternative);
   return output_387_reg_move (insn, operands);
 }
-  [(set_attr "type" "fmov,multi")
-   (set_attr "unit" "*,i387")
+  [(set_attr "type" "fmov,multi,multi,multi")
+   (set_attr "unit" "*,i387,i387,i387")
    (set_attr "mode" "SF")])
 
 (define_insn "*truncxfdf2_mixed"
-  [(set (match_operand:DF 0 "nonimmediate_operand" "=m,?fY2*r")
+  [(set (match_operand:DF 0 "nonimmediate_operand" "=m,?f,?Y2,?*r")
 	(float_truncate:DF
-	  (match_operand:XF 1 "register_operand" "f,f")))
-   (clobber (match_operand:DF 2 "memory_operand" "=X,m"))]
+	  (match_operand:XF 1 "register_operand"   "f ,f ,f  ,f")))
+   (clobber (match_operand:DF 2 "memory_operand"   "=X,m ,m  ,m"))]
   "TARGET_80387"
 {
   gcc_assert (!which_alternative);
   return output_387_reg_move (insn, operands);
 }
-  [(set_attr "type" "fmov,multi")
-   (set_attr "unit" "*,i387")
+  [(set_attr "type" "fmov,multi,multi,multi")
+   (set_attr "unit" "*,i387,i387,i387")
    (set_attr "mode" "DF")])
 
 (define_insn "truncxf<mode>2_i387_noop"
Index: testsuite/gcc.target/i386/pr39482.c
===================================================================
--- testsuite/gcc.target/i386/pr39482.c	(revision 0)
+++ testsuite/gcc.target/i386/pr39482.c	(revision 0)
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-mno-sse2" } */
+
+extern double log (double __x);
+
+double foo (unsigned long int m_liOutputBufferLen)
+{
+  return log ((double) m_liOutputBufferLen);
+}