xref: /aosp_15_r20/external/clang/test/CodeGen/bitfield-assign.c (revision 67e74705e28f6214e480b399dd47ea732279e315)
1*67e74705SXin Li /* Check that the result of a bitfield assignment is properly
2*67e74705SXin Li    truncated and does not generate a redundant load. */
3*67e74705SXin Li 
4*67e74705SXin Li /* Check that we get one load for each simple assign and two for the
5*67e74705SXin Li    compound assign (load the old value before the add then load again
6*67e74705SXin Li    to store back). Also check that our g0 pattern is good. */
7*67e74705SXin Li // RUN: %clang_cc1 -triple i386-unknown-unknown -emit-llvm -o %t %s
8*67e74705SXin Li // RUN: grep 'load ' %t | count 5
9*67e74705SXin Li // RUN: grep "@g0" %t | count 4
10*67e74705SXin Li 
11*67e74705SXin Li // Check that we got the right value.
12*67e74705SXin Li // RUN: %clang_cc1 -triple i386-unknown-unknown -O3 -emit-llvm -o %t %s
13*67e74705SXin Li // RUN: not grep 'load ' %t
14*67e74705SXin Li // RUN: not grep "@g0" %t
15*67e74705SXin Li 
16*67e74705SXin Li struct s0 {
17*67e74705SXin Li   int f0 : 2;
18*67e74705SXin Li   _Bool f1 : 1;
19*67e74705SXin Li   unsigned f2 : 2;
20*67e74705SXin Li };
21*67e74705SXin Li 
22*67e74705SXin Li int g0();
23*67e74705SXin Li 
f0(void)24*67e74705SXin Li void f0(void) {
25*67e74705SXin Li   struct s0 s;
26*67e74705SXin Li   if ((s.f0 = 3) != -1) g0();
27*67e74705SXin Li }
28*67e74705SXin Li 
f1(void)29*67e74705SXin Li void f1(void) {
30*67e74705SXin Li   struct s0 s;
31*67e74705SXin Li   if ((s.f1 = 3) != 1) g0();
32*67e74705SXin Li }
33*67e74705SXin Li 
f2(void)34*67e74705SXin Li void f2(void) {
35*67e74705SXin Li   struct s0 s;
36*67e74705SXin Li   if ((s.f2 = 3) != 3) g0();
37*67e74705SXin Li }
38*67e74705SXin Li 
f3(void)39*67e74705SXin Li void f3(void) {
40*67e74705SXin Li   struct s0 s;
41*67e74705SXin Li   // Just check this one for load counts.
42*67e74705SXin Li   s.f0 += 3;
43*67e74705SXin Li }
44*67e74705SXin Li 
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