Hi Rohit, [ Please CC: me on combine patches ].
On Tue, Feb 16, 2016 at 05:02:30AM +0000, Rohit Arul Raj D wrote: > This is related to the following bug: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60818 > > Test case: > unsigned int ou; > int jv(void) > { > unsigned int rg; > return rg < ou; > } > a) The test case passes with '-mno-isel' option. > The bug description has 2 test cases (comment #4) and both of them pass > with this option. It needs -m32 -misel -mno-mfcrf to fail. > Corresponding content of "op" which causes the ICE: > gdb) p debug_rtx (op) > (gtu:SI (reg:CC 166) ---------------------- (operator and mode doesn't match) > (const_int 0 [0])) That is invalid RTL for this target (should be CCUNS). Invalid RTL should not be passed to recog. > My initial fix was to have signed_scc_comparison_operator and > unsigned_scc_comparison_operator but that led to ICE from another stage of > combiner pass. So I thought it would be better to fix this at the stage where > the conditional mode is being wrongly set. Yes. Btw, please try to send email with lines < 76 chars or so. > (gdb) p debug_rtx (other_insn) > (insn 11 10 16 2 (set (reg:SI 165 [ D.2339+-3 ]) > (if_then_else:SI (ne (reg:CC 166) > (const_int 0 [0])) > (reg:SI 168) > (reg:SI 167))) test.c:7 317 {isel_unsigned_si} > (expr_list:REG_DEAD (reg:SI 168) > (expr_list:REG_DEAD (reg:SI 167) > (expr_list:REG_DEAD (reg:CC 166) > (expr_list:REG_EQUAL (gtu:SI (reg:CC 166) > (const_int 0 [0])) > (nil)))))) The REG_EQUAL there is bad already. Where does that come from? > + else > + { > + SUBST_MODE (regno_reg_rtx[regno], new_mode); > + new_dest = regno_reg_rtx[regno]; > + } > + SUBST (SET_DEST (i2mod_new_rhs), new_dest); > + } Let's not SUBST outside of try_combine please. It probably works, but there is enough action-at-a-distance as it is. Segher
