| Message ID | 20190220223214.GQ2135@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series | Fix ICE with _Complex type punning expansion (PR middle-end/89412) | expand |
On 2/20/19 3:32 PM, Jakub Jelinek wrote: > Hi! > > On the following testcase we ICE in simplify_gen_subreg, when result has > BLKmode and we want to convert it to some complex mode (e.g. DCmode or > in theory XCmode or TCmode too). > Such SUBREGs are invalid, but BLKmode can only live in memory and when it > is a MEM, we don't really need to create a subreg, we can change_address > and just load it as if it is a complex MEM. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? > > 2019-02-20 Jakub Jelinek <jakub@redhat.com> > > PR middle-end/89412 > * expr.c (expand_assignment): If result is a MEM, use change_address > instead of simplify_gen_subreg. > > * gcc.c-torture/compile/pr89412.c: New test. OK Jeff
--- gcc/expr.c.jj 2019-02-16 12:19:37.602192262 +0100 +++ gcc/expr.c 2019-02-20 16:29:39.261497006 +0100 @@ -5211,9 +5211,13 @@ expand_assignment (tree to, tree from, b } else { - rtx from_rtx - = simplify_gen_subreg (to_mode, result, - TYPE_MODE (TREE_TYPE (from)), 0); + rtx from_rtx; + if (MEM_P (result)) + from_rtx = change_address (result, to_mode, NULL_RTX); + else + from_rtx + = simplify_gen_subreg (to_mode, result, + TYPE_MODE (TREE_TYPE (from)), 0); if (from_rtx) { emit_move_insn (XEXP (to_rtx, 0), --- gcc/testsuite/gcc.c-torture/compile/pr89412.c.jj 2019-02-20 16:30:47.722387639 +0100 +++ gcc/testsuite/gcc.c-torture/compile/pr89412.c 2019-02-20 16:31:29.288714080 +0100 @@ -0,0 +1,16 @@ +/* PR middle-end/89412 */ + +struct S { double a, b; } d; +int e; +double f; + +void +foo () +{ + _Complex double h; + while (e) + { + f = h; + *(struct S *) &h = d; + } +}