1 #include <stdint.h> 2 #include <stdio.h> 3 4 typedef struct { 5 uint64_t high; 6 uint64_t low; 7 } quad_word; 8 9 void 10 test(quad_word op1_init, uint64_t op2_init, quad_word op3_init) 11 { 12 int cc; // unused 13 quad_word op1 = op1_init; 14 uint64_t op2 = op2_init; 15 quad_word op3 = op3_init; 16 17 __asm__ volatile ( 18 "lmg %%r0,%%r1,%1\n\t" 19 "lmg %%r2,%%r3,%3\n\t" 20 "cds %%r0,%%r2,%2\n\t" // cds 1st,3rd,2nd 21 "stmg %%r0,%%r1,%1\n" // store r0,r1 to op1 22 "stmg %%r2,%%r3,%3\n" // store r2,r3 to op3 23 : "=d" (cc), "+QS" (op1), "+QS" (op2), "+QS" (op3) 24 : 25 : "r0", "r1", "r2", "r3", "cc"); 26 27 } 28 29 // Return a quad-word that only bits low[32:63] are undefined 30 quad_word 31 make_undefined(void) 32 { 33 quad_word val; 34 35 val.high = 0; 36 val.low |= 0xFFFFFFFF00000000ull; 37 38 return val; 39 } 40 41 void op1_undefined(void) 42 { 43 quad_word op1, op3; 44 uint64_t op2; 45 46 // op1 undefined 47 op1 = make_undefined(); 48 op2 = 42; 49 op3.high = op3.low = 0xdeadbeefdeadbabeull; 50 test(op1, op2, op3); // complaint 51 } 52 53 void op2_undefined(void) 54 { 55 quad_word op1, op3; 56 uint64_t op2; 57 58 op1.high = op1.low = 42; 59 // op2 undefined 60 op3.high = op3.low = 0xdeadbeefdeadbabeull; 61 test(op1, op2, op3); // complaint 62 } 63 64 void op3_undefined(void) 65 { 66 quad_word op1, op3; 67 uint64_t op2; 68 69 op1.high = op1.low = 42; 70 op2 = 100; 71 op3 = make_undefined(); 72 test(op1, op2, op3); // no complaint; op3 is just copied around 73 } 74 75 int main () 76 { 77 op1_undefined(); 78 op2_undefined(); 79 op3_undefined(); 80 81 return 0; 82 } 83
