[Bug c/80376] New: Some vec_xxpermdi usage lead to ICE

[lu_zero at gentoo dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80376

            Bug ID: 80376
           Summary: Some vec_xxpermdi usage lead to ICE
           Product: gcc
           Version: 6.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: lu_zero at gentoo dot org
  Target Milestone: ---

Testcase:

#include <altivec.h>
#include <stdio.h>

int main(void) {

vector unsigned int a = { 1, 2, 3, 4 };
vector unsigned int b = { -1, -2, -3, -4 };
unsigned int c[4], i, j;

for (j = 0; j < 4; j++) {
    printf("%d -> ", j);
    vec_vsx_st(vec_xxpermdi(a, b, j), 0, c);
    for (i = 0; i < 4; i++) {
        printf("%d ", c[i]);
    }
    printf("\n");
}

return 0;
}


compiler log:

/tmp/t.c: In function ‘main’:
/tmp/t.c:12:5: internal compiler error: in copy_to_mode_reg, at explow.c:601
     vec_vsx_st(vec_xxpermdi(a, b, j), 0, c);
     ^~~~~~~~~~
0x103b737f copy_to_mode_reg(machine_mode, rtx_def*)
        ../../src/gcc/explow.c:601
0x10a0ae0f rs6000_expand_ternop_builtin
        ../../src/gcc/config/rs6000/rs6000.c:14234
0x10a0ae0f rs6000_expand_builtin
        ../../src/gcc/config/rs6000/rs6000.c:15658
0x1028cf9f expand_builtin(tree_node*, rtx_def*, rtx_def*, machine_mode, int)
        ../../src/gcc/builtins.c:5624
0x103d12ff expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        ../../src/gcc/expr.c:10598
0x103dc017 store_expr_with_bounds(tree_node*, rtx_def*, int, bool, bool,
tree_node*)
        ../../src/gcc/expr.c:5406
0x103dd3cb expand_assignment(tree_node*, tree_node*, bool)
        ../../src/gcc/expr.c:5175
0x102aec73 expand_call_stmt
        ../../src/gcc/cfgexpand.c:2658
0x102aec73 expand_gimple_stmt_1
        ../../src/gcc/cfgexpand.c:3548
0x102aec73 expand_gimple_stmt
        ../../src/gcc/cfgexpand.c:3714
0x102b1937 expand_gimple_basic_block
        ../../src/gcc/cfgexpand.c:5720
0x102b6f87 execute
        ../../src/gcc/cfgexpand.c:6335