none/tests/ppc32/ldstrev.c

   1
   2 #include <stdio.h>
   3
   4 typedef  unsigned int    UInt;
   5 typedef  unsigned short  UShort;
   6
   7 UInt read16le ( void* a )
   8 {
   9   UInt res;
  10   __asm volatile(
  11     "   lhbrx   %0,0,%1         \n"     // Get half word and reverse the bytes
  12     : "=b" (res)  // %0 - Output operand
  13     : "b" (a)        // %1 - Input operand
  14     : "memory"       // Consider memory clobberred for aliasing
  15   );
  16   return res;
  17 }
  18
  19 UInt read16be ( void* a )
  20 {
  21   UInt res;
  22   __asm volatile(
  23     "   lhzx   %0,0,%1         \n"     // Get half word and reverse the bytes
  24     : "=b" (res)  // %0 - Output operand
  25     : "b" (a)        // %1 - Input operand
  26     : "memory"       // Consider memory clobberred for aliasing
  27   );
  28   return res;
  29 }
  30
  31 UInt read32le ( void* a )
  32 {
  33   UInt res;
  34   __asm volatile(
  35     "   lwbrx   %0,0,%1         \n"     // Get half word and reverse the bytes
  36     : "=b" (res)  // %0 - Output operand
  37     : "b" (a)        // %1 - Input operand
  38     : "memory"       // Consider memory clobberred for aliasing
  39   );
  40   return res;
  41 }
  42
  43 UInt read32be ( void* a )
  44 {
  45   UInt res;
  46   __asm volatile(
  47     "   lwzx   %0,0,%1         \n"     // Get half word and reverse the bytes
  48     : "=b" (res)  // %0 - Output operand
  49     : "b" (a)        // %1 - Input operand
  50     : "memory"       // Consider memory clobberred for aliasing
  51   );
  52   return res;
  53 }
  54
  55 void write16be ( void* a, UInt data )
  56 {
  57   __asm volatile(
  58     "  sthx %0,0,%1\n"
  59     :
  60     : "b" (data), "b" (a)
  61     : "memory"
  62   );
  63 }
  64
  65 void write16le ( void* a, UInt data )
  66 {
  67   __asm volatile(
  68     "  sthbrx %0,0,%1\n"
  69     :
  70     : "b" (data), "b" (a)
  71     : "memory"
  72   );
  73 }
  74
  75 void write32be ( void* a, UInt data )
  76 {
  77   __asm volatile(
  78     "  stwx %0,0,%1\n"
  79     :
  80     : "b" (data), "b" (a)
  81     : "memory"
  82   );
  83 }
  84
  85 void write32le ( void* a, UInt data )
  86 {
  87   __asm volatile(
  88     "  stwbrx %0,0,%1\n"
  89     :
  90     : "b" (data), "b" (a)
  91     : "memory"
  92   );
  93 }
  94
  95 int main ( void )
  96 {
  97    UInt foo = 0x12345678;
  98    printf("ld be16 0x%08x\n", read16be( &foo ));
  99    printf("ld le16 0x%08x\n", read16le( &foo ));
 100    printf("ld be32 0x%08x\n", read32be( &foo ));
 101    printf("ld le32 0x%08x\n", read32le( &foo ));
 102
 103    foo = 0x12345678; write16be( &foo, 0xABCD );
 104    printf("st be16 0x%08x\n", foo);
 105
 106    foo = 0x12345678; write16le( &foo, 0xABCD );
 107    printf("st le16 0x%08x\n", foo);
 108
 109    foo = 0x12345678; write32be( &foo, 0xABCD1425 );
 110    printf("st be32 0x%08x\n", foo);
 111
 112    foo = 0x12345678; write32le( &foo, 0xABCD1425 );
 113    printf("st le32 0x%08x\n", foo);
 114
 115    return 0;
 116 }