sparse/sparse-dev.git - Sparse's development tree with unstable git history

Age	Commit message (Collapse)	Author	Files	Lines
2018-08-24	simplify AND(SHIFT(a \| b, S), M)	Luc Van Oostenryck	1	-1/+0
	The simplification of AND(SHIFT(a \| b, S), M) can be done by combining the mask M with the effective mask corresponding to SHIFT(_, S). This instruction pattern is generated when accessing bitfields, for example, code like: struct u { unsigned int :2; unsigned int f:3; }; int bfu(struct u s, int a) { s.f = a; return s.f; } is now simplified into the minimal: bfu: and.32 %r11 <- %arg2, $7 ret.32 %r11 The simplification is done by introducing a small helper, simplify_mask_shift(), doing the pattern matching and then calling simplify_mask_shift_or() with the mask M. Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
2018-08-22	add testcases for bitfield & AND/OR simplification	Luc Van Oostenryck	1	-0/+22
	The extraction & insertion of bitfields is made of relatively complex combinations of SHL/LSR/AND/OR and TRUNC/ZEXT/SEXT. Add a few testcases showing the effectiveness of their simplification and to catch possible future regressions. Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>