*** empty log message ***

From-SVN: r381

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index cd81f69990123dc8c0967fa901546b51a4988012..6aed00d1d6b6bfedc5506716d272ac8caf73926d 100644 (file)
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -49,7 +49,7 @@ static char *qi_high_reg_name[] = QI_HIGH_REGISTER_NAMES;
 enum reg_class regclass_map[FIRST_PSEUDO_REGISTER] =
 {
   /* ax, dx, cx, bx */
-  AREG, DREG, CREG, Q_REGS,
+  AREG, DREG, CREG, BREG,
   /* si, di, bp, sp */
   SIREG, DIREG, INDEX_REGS, GENERAL_REGS,
   /* FP registers */

diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index c0cd287b3d2f0c5d66baf1b8ed168239639771e9..e24cbd149c8cfd7c93c72adf62c01e8318682c87 100644 (file)
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -309,13 +309,16 @@ extern int target_flags;
    in a smaller-numbered class.
 
    For any two classes, it is very desirable that there be another
-   class that represents their union.  */
-   
+   class that represents their union.
+
+   It might seem that class BREG is unnecessary, since no useful 386
+   opcode needs reg %ebx.  But some systems pass args to the OS in ebx,
+   and the "b" register constraint is useful in asms for syscalls.  */
 
 enum reg_class
 {
   NO_REGS,
-  AREG, DREG, CREG,
+  AREG, DREG, CREG, BREG,
   Q_REGS,                      /* %eax %ebx %ecx %edx */
   SIREG, DIREG,
   INDEX_REGS,                  /* %eax %ebx %ecx %edx %esi %edi %ebp */
@@ -331,7 +334,7 @@ enum reg_class
 
 #define REG_CLASS_NAMES \
 {  "NO_REGS",                          \
-   "AREG", "DREG", "CREG",             \
+   "AREG", "DREG", "CREG", "BREG",     \
    "Q_REGS",                           \
    "SIREG", "DIREG",                   \
    "INDEX_REGS",                       \
@@ -346,7 +349,7 @@ enum reg_class
 
 #define REG_CLASS_CONTENTS \
 {      0,                                                      \
-     0x1,    0x2,  0x4,                /* AREG, DREG, CREG */          \
+     0x1,    0x2,  0x4,         0x8,   /* AREG, DREG, CREG, BREG */    \
      0xf,                      /* Q_REGS */                    \
     0x10,   0x20,              /* SIREG, DIREG */              \
  0x1007f,                      /* INDEX_REGS */                \
@@ -409,6 +412,7 @@ extern enum reg_class regclass_map[FIRST_PSEUDO_REGISTER];
    (C) == 't' ? FP_TOP_REG :           \
    (C) == 'u' ? FP_SECOND_REG :                \
    (C) == 'a' ? AREG :                 \
+   (C) == 'b' ? BREG :                 \
    (C) == 'c' ? CREG :                 \
    (C) == 'd' ? DREG :                 \
    (C) == 'D' ? DIREG :                        \