[PATCH, i386]: Fix PR 68263, Vector "*mov_internal" fails to handle misaligned load/store from reload

[Uros Bizjak]

Hello!

Attached patch fixes PR 68263. IAMCU ABI doesn't guarantee any
alignment, so we have to emit unaligned moves for SSE or AVX unaligned
operands.

2015-11-17  Uros Bizjak  <ubiz...@gmail.com>

    PR target/68263
    * config/i386/i386.h (BIGGEST_ALIGNMENT): Always define
    to 32 for IAMCU.
    * config/i386/sse.md (*mov<mode>_internal): Always enable
    AVX and SSE unaligned moves for IAMCU.

Patch fixes gcc.target/i386/iamcu/test_passing_floats.c execution
testsuite failure.

Patch was also tested by HJ on IAMCU target.

Bootstrapped and regression tested on x86_64-linux-gnu {,-m32},
committed to mainline SVN.

Uros.

Index: config/i386/i386.h
===================================================================
--- config/i386/i386.h  (revision 230454)
+++ config/i386/i386.h  (working copy)
@@ -814,7 +814,7 @@
    TARGET_ABSOLUTE_BIGGEST_ALIGNMENT.  */
 
 #define BIGGEST_ALIGNMENT \
-  (TARGET_AVX512F ? 512 : (TARGET_AVX ? 256 : (TARGET_IAMCU ? 32 : 128)))
+  (TARGET_IAMCU ? 32 : (TARGET_AVX512F ? 512 : (TARGET_AVX ? 256 : 128)))
 
 /* Maximum stack alignment.  */
 #define MAX_STACK_ALIGNMENT MAX_OFILE_ALIGNMENT
Index: config/i386/sse.md
===================================================================
--- config/i386/sse.md  (revision 230454)
+++ config/i386/sse.md  (working copy)
@@ -892,30 +892,30 @@
        case MODE_V16SF:
        case MODE_V8SF:
        case MODE_V4SF:
-         if (TARGET_AVX
+         if ((TARGET_AVX || TARGET_IAMCU)
              && (misaligned_operand (operands[0], <MODE>mode)
                  || misaligned_operand (operands[1], <MODE>mode)))
-           return "vmovups\t{%1, %0|%0, %1}";
+           return "%vmovups\t{%1, %0|%0, %1}";
          else
            return "%vmovaps\t{%1, %0|%0, %1}";
 
        case MODE_V8DF:
        case MODE_V4DF:
        case MODE_V2DF:
-         if (TARGET_AVX
+         if ((TARGET_AVX || TARGET_IAMCU)
              && (misaligned_operand (operands[0], <MODE>mode)
                  || misaligned_operand (operands[1], <MODE>mode)))
-           return "vmovupd\t{%1, %0|%0, %1}";
+           return "%vmovupd\t{%1, %0|%0, %1}";
          else
            return "%vmovapd\t{%1, %0|%0, %1}";
 
        case MODE_OI:
        case MODE_TI:
-         if (TARGET_AVX
+         if ((TARGET_AVX || TARGET_IAMCU)
              && (misaligned_operand (operands[0], <MODE>mode)
                  || misaligned_operand (operands[1], <MODE>mode)))
            return TARGET_AVX512VL ? "vmovdqu64\t{%1, %0|%0, %1}"
-                                  : "vmovdqu\t{%1, %0|%0, %1}";
+                                  : "%vmovdqu\t{%1, %0|%0, %1}";
          else
            return TARGET_AVX512VL ? "vmovdqa64\t{%1, %0|%0, %1}"
                                   : "%vmovdqa\t{%1, %0|%0, %1}";