On Thu, Mar 21, 2024 at 5:07 PM Andrew Stubbs <a...@baylibre.com> wrote: > > On 21/03/2024 15:18, Richard Biener wrote: > > On Thu, Mar 21, 2024 at 3:23 PM Andrew Stubbs <a...@baylibre.com> wrote: > >> > >> My previous patch to fix this problem with xor was rejected because we > >> want to fix these issues only at the point of use. That patch produced > >> slightly better code, in this example, but this works too.... > >> > >> These patches fix up a failure in testcase vect/tsvc/vect-tsvc-s278.c when > >> configured to use V32 instead of V64 (I plan to do this for RDNA devices). > >> > >> The problem was that a "not" operation on the mask inadvertently enabled > >> inactive lanes 31-63 and corrupted the output. The fix is to adjust the > >> mask > >> when calling internal functions (in this case COND_MINUS), when doing > >> masked > >> loads and stores, and when doing conditional jumps. > >> > >> OK for mainline? > >> > >> Andrew > >> > >> gcc/ChangeLog: > >> > >> * dojump.cc (do_compare_rtx_and_jump): Clear excess bits in vector > >> bitmaps. > >> * internal-fn.cc (expand_fn_using_insn): Likewise. > >> (add_mask_and_len_args): Likewise. > >> --- > >> gcc/dojump.cc | 16 ++++++++++++++++ > >> gcc/internal-fn.cc | 26 ++++++++++++++++++++++++++ > >> 2 files changed, 42 insertions(+) > >> > >> diff --git a/gcc/dojump.cc b/gcc/dojump.cc > >> index 88600cb42d3..8df86957e83 100644 > >> --- a/gcc/dojump.cc > >> +++ b/gcc/dojump.cc > >> @@ -1235,6 +1235,22 @@ do_compare_rtx_and_jump (rtx op0, rtx op1, enum > >> rtx_code code, int unsignedp, > >> } > >> } > >> > >> + if (val > >> + && VECTOR_BOOLEAN_TYPE_P (TREE_TYPE (val)) > >> + && SCALAR_INT_MODE_P (mode)) > >> + { > >> + auto nunits = TYPE_VECTOR_SUBPARTS (TREE_TYPE (val)).to_constant > >> (); > >> + if (maybe_ne (GET_MODE_PRECISION (mode), nunits)) > >> + { > >> + op0 = expand_binop (mode, and_optab, op0, > >> + GEN_INT ((HOST_WIDE_INT_1U << nunits) - > >> 1), > >> + NULL_RTX, true, OPTAB_WIDEN); > >> + op1 = expand_binop (mode, and_optab, op1, > >> + GEN_INT ((HOST_WIDE_INT_1U << nunits) - > >> 1), > >> + NULL_RTX, true, OPTAB_WIDEN); > >> + } > >> + } > >> + > > > > Can we then remove the same code from do_compare_and_jump before the call to > > do_compare_rtx_and_jump? > > It's called from do_jump. > > > I'll note that we don't pass 'val' there and > > 'val' is unfortunately > > not documented - what's it supposed to be? I think I placed the original > > fix in > > do_compare_and_jump because we have the full into available there. So > > what's the > > do_compare_rtx_and_jump caller that needs fixing as well? (IMHO keying on > > 'val' > > looks fragile) > > "val" is the tree expression from which the rtx op0 was expanded. It's > optional, but it's used in emit_cmp_and_jump_insns to determine whether > the target supports tbranch (according to a comment). > > I think it would be safe to remove your code as that path does path > "treeop0" to "val". > > WDYT?
Looks like a bit of a mess, but yes, I think that sounds good. Thanks, Richard. > > The other hunks below are OK. > > Thanks. > > Andrew > > > Thanks, > > Richard. > > > >> emit_cmp_and_jump_insns (op0, op1, code, size, mode, unsignedp, > >> val, > >> if_true_label, prob); > >> } > >> diff --git a/gcc/internal-fn.cc b/gcc/internal-fn.cc > >> index fcf47c7fa12..5269f0ac528 100644 > >> --- a/gcc/internal-fn.cc > >> +++ b/gcc/internal-fn.cc > >> @@ -245,6 +245,18 @@ expand_fn_using_insn (gcall *stmt, insn_code icode, > >> unsigned int noutputs, > >> && SSA_NAME_IS_DEFAULT_DEF (rhs) > >> && VAR_P (SSA_NAME_VAR (rhs))) > >> create_undefined_input_operand (&ops[opno], TYPE_MODE (rhs_type)); > >> + else if (VECTOR_BOOLEAN_TYPE_P (rhs_type) > >> + && SCALAR_INT_MODE_P (TYPE_MODE (rhs_type)) > >> + && maybe_ne (GET_MODE_PRECISION (TYPE_MODE (rhs_type)), > >> + TYPE_VECTOR_SUBPARTS (rhs_type).to_constant > >> ())) > >> + { > >> + /* Ensure that the vector bitmasks do not have excess bits. */ > >> + int nunits = TYPE_VECTOR_SUBPARTS (rhs_type).to_constant (); > >> + rtx tmp = expand_binop (TYPE_MODE (rhs_type), and_optab, rhs_rtx, > >> + GEN_INT ((HOST_WIDE_INT_1U << nunits) - > >> 1), > >> + NULL_RTX, true, OPTAB_WIDEN); > >> + create_input_operand (&ops[opno], tmp, TYPE_MODE (rhs_type)); > >> + } > >> else > >> create_input_operand (&ops[opno], rhs_rtx, TYPE_MODE (rhs_type)); > >> opno += 1; > >> @@ -312,6 +324,20 @@ add_mask_and_len_args (expand_operand *ops, unsigned > >> int opno, gcall *stmt) > >> { > >> tree mask = gimple_call_arg (stmt, mask_index); > >> rtx mask_rtx = expand_normal (mask); > >> + > >> + tree mask_type = TREE_TYPE (mask); > >> + if (VECTOR_BOOLEAN_TYPE_P (mask_type) > >> + && SCALAR_INT_MODE_P (TYPE_MODE (mask_type)) > >> + && maybe_ne (GET_MODE_PRECISION (TYPE_MODE (mask_type)), > >> + TYPE_VECTOR_SUBPARTS (mask_type).to_constant ())) > >> + { > >> + /* Ensure that the vector bitmasks do not have excess bits. */ > >> + int nunits = TYPE_VECTOR_SUBPARTS (mask_type).to_constant (); > >> + mask_rtx = expand_binop (TYPE_MODE (mask_type), and_optab, > >> mask_rtx, > >> + GEN_INT ((HOST_WIDE_INT_1U << nunits) - > >> 1), > >> + NULL_RTX, true, OPTAB_WIDEN); > >> + } > >> + > >> create_input_operand (&ops[opno++], mask_rtx, > >> TYPE_MODE (TREE_TYPE (mask))); > >> } > >> -- > >> 2.41.0 > >> >