From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by sourceware.org (Postfix) with ESMTPS id 608983858039 for ; Mon, 10 May 2021 13:29:10 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 608983858039 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=rguenther@suse.de X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 31893B246; Mon, 10 May 2021 13:29:09 +0000 (UTC) Date: Mon, 10 May 2021 15:29:09 +0200 (CEST) From: Richard Biener To: Tamar Christina cc: "gcc-patches@gcc.gnu.org" , nd Subject: RE: [PATCH 1/4]middle-end Vect: Add support for dot-product where the sign for the multiplicant changes. In-Reply-To: Message-ID: References: User-Agent: Alpine 2.21 (LSU 202 2017-01-01) MIME-Version: 1.0 X-Spam-Status: No, score=-11.2 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, KAM_LOTSOFHASH, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 May 2021 13:29:14 -0000 On Mon, 10 May 2021, Tamar Christina wrote: > > > > -----Original Message----- > > From: Richard Biener > > Sent: Monday, May 10, 2021 12:40 PM > > To: Tamar Christina > > Cc: gcc-patches@gcc.gnu.org; nd > > Subject: RE: [PATCH 1/4]middle-end Vect: Add support for dot-product > > where the sign for the multiplicant changes. > > > > On Fri, 7 May 2021, Tamar Christina wrote: > > > > > Hi Richi, > > > > > > > -----Original Message----- > > > > From: Richard Biener > > > > Sent: Friday, May 7, 2021 12:46 PM > > > > To: Tamar Christina > > > > Cc: gcc-patches@gcc.gnu.org; nd > > > > Subject: Re: [PATCH 1/4]middle-end Vect: Add support for dot-product > > > > where the sign for the multiplicant changes. > > > > > > > > On Wed, 5 May 2021, Tamar Christina wrote: > > > > > > > > > Hi All, > > > > > > > > > > This patch adds support for a dot product where the sign of the > > > > > multiplication arguments differ. i.e. one is signed and one is > > > > > unsigned but the precisions are the same. > > > > > > > > > > #define N 480 > > > > > #define SIGNEDNESS_1 unsigned > > > > > #define SIGNEDNESS_2 signed > > > > > #define SIGNEDNESS_3 signed > > > > > #define SIGNEDNESS_4 unsigned > > > > > > > > > > SIGNEDNESS_1 int __attribute__ ((noipa)) f (SIGNEDNESS_1 int res, > > > > > SIGNEDNESS_3 char *restrict a, > > > > > SIGNEDNESS_4 char *restrict b) > > > > > { > > > > > for (__INTPTR_TYPE__ i = 0; i < N; ++i) > > > > > { > > > > > int av = a[i]; > > > > > int bv = b[i]; > > > > > SIGNEDNESS_2 short mult = av * bv; > > > > > res += mult; > > > > > } > > > > > return res; > > > > > } > > > > > > > > > > The operations are performed as if the operands were extended to a > > > > > 32-bit > > > > value. > > > > > As such this operation isn't valid if there is an intermediate > > > > > conversion to an unsigned value. i.e. if SIGNEDNESS_2 is unsigned. > > > > > > > > > > more over if the signs of SIGNEDNESS_3 and SIGNEDNESS_4 are > > > > > flipped the same optab is used but the operands are flipped in the > > > > > optab > > > > expansion. > > > > > > > > > > To support this the patch extends the dot-product detection to > > > > > optionally ignore operands with different signs and stores this > > > > > information in the optab subtype which is now made a bitfield. > > > > > > > > > > The subtype can now additionally controls which optab an EXPR can > > > > > expand > > > > to. > > > > > > > > > > Bootstrapped Regtested on aarch64-none-linux-gnu and no issues. > > > > > > > > > > Ok for master? > > > > > > > > > > Thanks, > > > > > Tamar > > > > > > > > > > gcc/ChangeLog: > > > > > > > > > > * optabs.def (usdot_prod_optab): New. > > > > > * doc/md.texi: Document it. > > > > > * optabs-tree.c (optab_for_tree_code): Support usdot_prod_optab. > > > > > * optabs-tree.h (enum optab_subtype): Likewise. > > > > > * optabs.c (expand_widen_pattern_expr): Likewise. > > > > > * tree-cfg.c (verify_gimple_assign_ternary): Likewise. > > > > > * tree-vect-loop.c (vect_determine_dot_kind): New. > > > > > (vectorizable_reduction): Query dot-product kind. > > > > > * tree-vect-patterns.c (vect_supportable_direct_optab_p): Take > > > > optional > > > > > optab subtype. > > > > > (vect_joust_widened_type, vect_widened_op_tree): Optionally > > > > ignore > > > > > mismatch types. > > > > > (vect_recog_dot_prod_pattern): Support usdot_prod_optab. > > > > > > > > > > --- inline copy of patch -- > > > > > diff --git a/gcc/doc/md.texi b/gcc/doc/md.texi index > > > > > > > > > > > d166a0debedf4d8edf55c842bcf4ff4690b3e9ce..baf20416e63745097825fc30fd > > > > f2 > > > > > e66bc80d7d23 100644 > > > > > --- a/gcc/doc/md.texi > > > > > +++ b/gcc/doc/md.texi > > > > > @@ -5440,11 +5440,13 @@ Like @samp{fold_left_plus_@var{m}}, but > > > > takes > > > > > an additional mask operand @item @samp{sdot_prod@var{m}} > > @cindex > > > > > @code{udot_prod@var{m}} instruction pattern @itemx > > > > > @samp{udot_prod@var{m}} > > > > > +@cindex @code{usdot_prod@var{m}} instruction pattern @itemx > > > > > +@samp{usdot_prod@var{m}} > > > > > Compute the sum of the products of two signed/unsigned elements. > > > > > -Operand 1 and operand 2 are of the same mode. Their product, > > > > > which is of a -wider mode, is computed and added to operand 3. > > > > > Operand 3 is of a mode equal or -wider than the mode of the > > > > > product. The result is placed in operand 0, which -is of the same mode > > as operand 3. > > > > > +Operand 1 and operand 2 are of the same mode but may differ in > > signs. > > > > > +Their product, which is of a wider mode, is computed and added to > > > > operand 3. > > > > > +Operand 3 is of a mode equal or wider than the mode of the product. > > > > > +The result is placed in operand 0, which is of the same mode as > > operand 3. > > > > > > > > This doesn't really say what the 's', 'u' and 'us' specify. Since > > > > we're doing a widen multiplication and then a non-widening addition > > > > we only need to know the effective sign of the multiplication so I think > > the existing 's' and 'u' > > > > are enough to cover all cases? > > > > > > The existing 's' and 'u' enforce that both operands of the > > > multiplication are of the same sign. So for e.g. 'u' both operand must be > > unsigned. > > > > > > In the `us` case one can be signed and one unsigned. Operationally > > > this does a sign extension to the wider type for the signed value, and > > > the unsigned value gets zero extended first, and then converts it to > > > unsigned to perform the unsigned multiplication, conforming to the C > > promotion rules. > > > > > > TL;DR; Without a new optab I can't tell during expansion which > > > semantic the operation had at the gimple/C level as modes don't carry signs. > > > > > > Long version: > > > > > > The problem with using the existing patterns, because of their > > > enforcement of `av` and `bv` being the same sign is that we can't > > > remove the explicit sign extensions, but the multiplication must be done on > > the sign/zero extended char input in the same sign. > > > > > > Which means (unless I am mistaken) to get the correct result, you > > > can't use neither `udot` nor `sdot` as semantically these would zero > > > or sign extend both operands from char to int to perform the > > > multiplication in the same sigh. Whereas in this case, one parameter is zero > > and one parameter is sign extended and the result is always an unsigned > > number. > > > > > > So basically > > > > > > udot == > > > c = zero-ext (a) * zero-ext (b) > > > sdot == > > > c = sign-ext (a) * sign-ext (b) > > > usdot == > > > c = ((unsigned-conv) sign-ext (a)) * zero-ext (b) > > > > > > So semantically the existing optabs won't fit here. udot would > > > internally promote to unsigned types before the multiplication so the > > > result of the multiplication would be wrong. sdot would promote both to > > signed and do signed multiplication, so the result is also wrong. > > > > > > Now if I relax the constraint on the signs of udot and sdot there are two > > problems: > > > RTL Modes don't contain signs. So a target can't tell me how the operands > > will be promoted. > > > So: > > > > > > 1) I can't really check which semantics the target will adhere to on > > expansion. > > > 2) at expand time I have no way to differentiate between the two > > instructions variants, given just modes > > > I can't tell whether I expand to the normal dot-product or the new > > instruction. > > > > Ah, OK. Indeed with such a weird instruction the new variant makes sense. > > Still can you please amend the optab documentation to say which operand is > > unsigned and which is signed? Just 'may differ in signs' > > is bad. > > Sure, will expand on it. > > > > > Since the multiplication is commutative I wonder why you need to handle > > both signed_to_unsigned and unsigned_to_signed - we should just enforce > > a canonical order (like the optab does). > > Sure, I thought it would have been better to change the order at expand time, > but can do so at detection time. > > > I also think it's a particular bad fit for > > the bad optab_for_tree_code API - would any of that improve when using a > > direct internal function here? > > Somewhat, but this has considerable knock on effects, e.g. currently DOT_PROD is > treated as a widening operation and so is handled by supportable_widening_operation > which does not support calls. There's a significant number of places which work on the > tree EXPR (including constant folding) which all need to be changed. > > > In particular all the changes around > > optab_subtype look like they make a bad API worse ... at least a single > > optab_vector_mixed_sign should suffice here, no need to make it a flags > > kind. > > The reason I did so is because depending on where the query is done it does use > different subtypes currently. During detection it uses optab_default, and during > vectorization optab_vector. For this instruction this difference doesn't seem to be > used, but did not want to lose this information in case something depended on it. > > But can make it just one. > > > > > + /* If we have a sign changing dot product we need to check that the > > + promoted type if unsigned has at least the same precision as the > > final > > + type of the dot-product. */ > > + if (subtype != optab_default) > > + { > > + tree mult_type = TREE_TYPE (unprom_mult.op); > > + if (TYPE_SIGN (mult_type) == UNSIGNED > > + && TYPE_PRECISION (mult_type) < TYPE_PRECISION (type)) > > + return NULL; > > + } > > > > I don't understand this - how do we ever arrive at a result with less precision? > > The user could have manually truncated the results, i.e. in the detection code notice `mult` > > int av = a[i]; > int bv = b[i]; > SIGNEDNESS_2 short mult = av * bv; > res += mult; > > which is a short, so it's manually truncating the multiplication which > is done as int by the instruction. If `mult` is unsigned then it will > truncate the result if the signed input to usdot was negative, unless > the Intermediate calculation is of the same precision as the > instruction. i.e. if mult is unsigned int then there's no truncation > going on, it's casting from int to unsigned int so it's safe to use then > as the instruction does the same thing internally. It looks to me that we simply should only ever allow sing-changes from multiplication result to the sum. At least your example above is not special to mixed sign multiplications, no? > > And why's this not an issue for signed multiplication? > > It is, but in that case it's handled by the type jousting, which doesn't > allow the type mismatch. i.e. > > #define SIGNEDNESS_1 unsigned > #define SIGNEDNESS_2 unsigned > #define SIGNEDNESS_3 signed > #define SIGNEDNESS_4 signed > > SIGNEDNESS_1 int __attribute__ ((noipa)) > f (SIGNEDNESS_1 int res, SIGNEDNESS_3 char *restrict a, > SIGNEDNESS_4 char *restrict b) > { > for (__INTPTR_TYPE__ i = 0; i < N; ++i) > { > int av = a[i]; > int bv = b[i]; > SIGNEDNESS_2 short mult = av * bv; > res += mult; > } > return res; > } > > Is also not detected as a dot product. By adding the carve out to the > widen multiplication detection it now allows this case through so I > handle it in the detection code. Thinking about it now, it seems more > logical to add this case handling inside the type jousting code as I > don't think it's ever something you'd want. Yeah, I think we only need to look through sign changes on the multiplication result. > > Also... > > > > + /* If we have a sign changing dot-product the dot-product itself does > > any > > + sign conversions, so consume the type and use the unpromoted types. > > */ > > + tree mult_arg1, mult_arg2; > > + if (subtype == optab_default) > > + { > > + mult_arg1 = mult_oprnd[0]; > > + mult_arg2 = mult_oprnd[1]; > > + } > > + else > > + { > > + mult_arg1 = unprom0[0].op; > > + mult_arg2 = unprom0[1].op; > > + } > > pattern_stmt = gimple_build_assign (var, DOT_PROD_EXPR, > > - mult_oprnd[0], mult_oprnd[1], > > oprnd1); > > + mult_arg1, mult_arg2, oprnd1); > > > > I thought DOT_PROD always performs the promotion. Maybe mult_oprnd > > and unprom0 are just misnamed here? > > Somewhat, in a normal dot-product the sign of the multiplication are the > same here as the "unpromoted" types. So after vect_convert_input these > two types are the same. > > However because here the sign changes and to maintain the semantics of > the C code there's an extra conversion here to get the arguments in the > same sign. That needs to be stripped before given to the instruction > which does the conversion internally. Yes, but then why's that not done by the detection code? That is, does it (mis-)handle the (int)short_a * (int)(unsigned short)short_b where we'd want the mixed-sign handling and not strip the unsigned short conversion from short_b? Richard. > > Regards, > Tamar > > > > > Richard. > > > > > Regards, > > > Tamar > > > > > > > > > > > The tree.def docs say the sum is also possibly widening but I don't > > > > see this covered by the optab so we should eventually remove this > > > > feature from the tree side. In fact the tree-cfg.c verifier > > > > requires the addition to be not widening - thus only tree.def needs > > adjustment. > > > > > > > > > @cindex @code{ssad@var{m}} instruction pattern @item > > > > > @samp{ssad@var{m}} diff --git a/gcc/optabs-tree.h > > > > > b/gcc/optabs-tree.h index > > > > > > > > > > > c3aaa1a416991e856d3e24da45968a92ebada82c..ebc23ac86fe99057f375781c2f > > > > 19 > > > > > 90e0548ba08d 100644 > > > > > --- a/gcc/optabs-tree.h > > > > > +++ b/gcc/optabs-tree.h > > > > > @@ -27,11 +27,29 @@ along with GCC; see the file COPYING3. If not > > see > > > > > shift amount vs. machines that take a vector for the shift amount. > > > > > */ enum optab_subtype { > > > > > - optab_default, > > > > > - optab_scalar, > > > > > - optab_vector > > > > > + optab_default = 1 << 0, > > > > > + optab_scalar = 1 << 1, > > > > > + optab_vector = 1 << 2, > > > > > + optab_signed_to_unsigned = 1 << 3, optab_unsigned_to_signed = > > > > > + 1 << 4 > > > > > }; > > > > > > > > > > +/* Override the OrEqual-operator so we can use optab_subtype as a > > > > > +bit flag. */ inline enum optab_subtype& operator |= (enum > > > > optab_subtype& > > > > > +a, enum optab_subtype b) { > > > > > + return a = static_cast(static_cast(a) > > > > > + | static_cast(b)); > > > > > +} > > > > > + > > > > > +/* Override the Or-operator so we can use optab_subtype as a bit > > > > > +flag. */ inline enum optab_subtype operator | (enum > > > > > +optab_subtype a, enum optab_subtype b) { > > > > > + return static_cast(static_cast(a) > > > > > + | static_cast(b)); } > > > > > + > > > > > /* Return the optab used for computing the given operation on the > > > > > type > > > > given by > > > > > the second argument. The third argument distinguishes between > > > > > the > > > > types of > > > > > vector shifts and rotates. */ diff --git a/gcc/optabs-tree.c > > > > > b/gcc/optabs-tree.c index > > > > > > > > > > > 95ffe397c23e80c105afea52e9d47216bf52f55a..2f60004545defc53182e004eea > > > > 1e > > > > > 5c22b7453072 100644 > > > > > --- a/gcc/optabs-tree.c > > > > > +++ b/gcc/optabs-tree.c > > > > > @@ -127,7 +127,17 @@ optab_for_tree_code (enum tree_code code, > > > > const_tree type, > > > > > return TYPE_UNSIGNED (type) ? usum_widen_optab : > > > > > ssum_widen_optab; > > > > > > > > > > case DOT_PROD_EXPR: > > > > > - return TYPE_UNSIGNED (type) ? udot_prod_optab : > > sdot_prod_optab; > > > > > + { > > > > > + gcc_assert (subtype & optab_default > > > > > + || subtype & optab_vector > > > > > + || subtype & optab_signed_to_unsigned > > > > > + || subtype & optab_unsigned_to_signed); > > > > > + > > > > > + if (subtype & (optab_unsigned_to_signed | > > > > optab_signed_to_unsigned)) > > > > > + return usdot_prod_optab; > > > > > + > > > > > + return (TYPE_UNSIGNED (type) ? udot_prod_optab : > > > > sdot_prod_optab); > > > > > + } > > > > > > > > > > case SAD_EXPR: > > > > > return TYPE_UNSIGNED (type) ? usad_optab : ssad_optab; diff > > > > > --git a/gcc/optabs.c b/gcc/optabs.c index > > > > > > > > > > > f4614a394587787293dc8b680a38901f7906f61c..2e18b76de1412eab71971753ac > > > > 67 > > > > > 8597c0d00098 100644 > > > > > --- a/gcc/optabs.c > > > > > +++ b/gcc/optabs.c > > > > > @@ -262,6 +262,11 @@ expand_widen_pattern_expr (sepops ops, rtx > > > > > op0, > > > > rtx op1, rtx wide_op, > > > > > bool sbool = false; > > > > > > > > > > oprnd0 = ops->op0; > > > > > + if (nops >= 2) > > > > > + oprnd1 = ops->op1; > > > > > + if (nops >= 3) > > > > > + oprnd2 = ops->op2; > > > > > + > > > > > tmode0 = TYPE_MODE (TREE_TYPE (oprnd0)); > > > > > if (ops->code == VEC_UNPACK_FIX_TRUNC_HI_EXPR > > > > > || ops->code == VEC_UNPACK_FIX_TRUNC_LO_EXPR) @@ -285,6 > > > > +290,27 > > > > > @@ expand_widen_pattern_expr (sepops ops, rtx op0, rtx op1, rtx > > > > wide_op, > > > > > ? vec_unpacks_sbool_hi_optab : vec_unpacks_sbool_lo_optab); > > > > > sbool = true; > > > > > } > > > > > + else if (ops->code == DOT_PROD_EXPR) > > > > > + { > > > > > + enum optab_subtype subtype = optab_default; > > > > > + signop sign1 = TYPE_SIGN (TREE_TYPE (oprnd0)); > > > > > + signop sign2 = TYPE_SIGN (TREE_TYPE (oprnd1)); > > > > > + if (sign1 == sign2) > > > > > + ; > > > > > + else if (sign1 == SIGNED && sign2 == UNSIGNED) > > > > > + { > > > > > + subtype |= optab_signed_to_unsigned; > > > > > + /* Same as optab_unsigned_to_signed but flip the operands. */ > > > > > + std::swap (op0, op1); > > > > > + } > > > > > + else if (sign1 == UNSIGNED && sign2 == SIGNED) > > > > > + subtype |= optab_unsigned_to_signed; > > > > > + else > > > > > + gcc_unreachable (); > > > > > + > > > > > + widen_pattern_optab > > > > > + = optab_for_tree_code (ops->code, TREE_TYPE (oprnd0), subtype); > > > > > + } > > > > > else > > > > > widen_pattern_optab > > > > > = optab_for_tree_code (ops->code, TREE_TYPE (oprnd0), > > > > > optab_default); @@ -298,10 +324,7 @@ expand_widen_pattern_expr > > > > (sepops ops, rtx op0, rtx op1, rtx wide_op, > > > > > gcc_assert (icode != CODE_FOR_nothing); > > > > > > > > > > if (nops >= 2) > > > > > - { > > > > > - oprnd1 = ops->op1; > > > > > - tmode1 = TYPE_MODE (TREE_TYPE (oprnd1)); > > > > > - } > > > > > + tmode1 = TYPE_MODE (TREE_TYPE (oprnd1)); > > > > > else if (sbool) > > > > > { > > > > > nops = 2; > > > > > @@ -316,7 +339,6 @@ expand_widen_pattern_expr (sepops ops, rtx > > > > > op0, > > > > rtx op1, rtx wide_op, > > > > > { > > > > > gcc_assert (tmode1 == tmode0); > > > > > gcc_assert (op1); > > > > > - oprnd2 = ops->op2; > > > > > wmode = TYPE_MODE (TREE_TYPE (oprnd2)); > > > > > } > > > > > > > > > > diff --git a/gcc/optabs.def b/gcc/optabs.def index > > > > > > > > > > > b192a9d070b8aa72e5676b2eaa020b5bdd7ffcc8..f470c2168378cec840edf7fbd > > > > b7c > > > > > 18615baae928 100644 > > > > > --- a/gcc/optabs.def > > > > > +++ b/gcc/optabs.def > > > > > @@ -352,6 +352,7 @@ OPTAB_D (uavg_ceil_optab, "uavg$a3_ceil") > > > > OPTAB_D > > > > > (sdot_prod_optab, "sdot_prod$I$a") OPTAB_D (ssum_widen_optab, > > > > > "widen_ssum$I$a3") OPTAB_D (udot_prod_optab, "udot_prod$I$a") > > > > > +OPTAB_D (usdot_prod_optab, "usdot_prod$I$a") > > > > > OPTAB_D (usum_widen_optab, "widen_usum$I$a3") OPTAB_D > > > > (usad_optab, > > > > > "usad$I$a") OPTAB_D (ssad_optab, "ssad$I$a") diff --git > > > > > a/gcc/tree-cfg.c b/gcc/tree-cfg.c index > > > > > > > > > > > 7e3aae5f9c28a49feedc7cc66e8ac0d476b9f28a..58b55bb648ad97d514f1fa18bb > > > > 00 > > > > > 808fd2678b42 100644 > > > > > --- a/gcc/tree-cfg.c > > > > > +++ b/gcc/tree-cfg.c > > > > > @@ -4421,7 +4421,8 @@ verify_gimple_assign_ternary (gassign *stmt) > > > > > && !SCALAR_FLOAT_TYPE_P (rhs1_type)) > > > > > || (!INTEGRAL_TYPE_P (lhs_type) > > > > > && !SCALAR_FLOAT_TYPE_P (lhs_type)))) > > > > > - || !types_compatible_p (rhs1_type, rhs2_type) > > > > > + || (!types_compatible_p (rhs1_type, rhs2_type) > > > > > + && TYPE_SIGN (rhs1_type) == TYPE_SIGN (rhs2_type)) > > > > > > > > That's not restrictive enough. I suggest you use > > > > > > > > && element_precision (rhs1_type) != element_precision > > > > (rhs2_type) > > > > > > > > instead. > > > > > > > > As said, I'm not sure all the changes in this patch are required. > > > > > > > > Please elaborate. > > > > > > > > Thanks, > > > > Richard. > > > > > > > > > || !useless_type_conversion_p (lhs_type, rhs3_type) > > > > > || maybe_lt (GET_MODE_SIZE (element_mode (rhs3_type)), > > > > > 2 * GET_MODE_SIZE (element_mode (rhs1_type)))) > > > > diff --git > > > > > a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c index > > > > > > > > > > > 93fa2928e001c154bd4a9a73ac1dbbbf73c456df..cb8f5fbb6abca181c4171194d1 > > > > 9f > > > > > ec29ec6e4176 100644 > > > > > --- a/gcc/tree-vect-loop.c > > > > > +++ b/gcc/tree-vect-loop.c > > > > > @@ -6401,6 +6401,33 @@ build_vect_cond_expr (enum tree_code > > code, > > > > tree vop[3], tree mask, > > > > > } > > > > > } > > > > > > > > > > +/* Determine the optab_subtype to use for the given CODE and STMT. > > > > For > > > > > + most CODE this will be optab_vector, however for certain > > > > > + operations > > > > such as > > > > > + DOT_PROD_EXPR where the operation can different signs for the > > > > operands we > > > > > + need to be able to pick the right optabs. */ > > > > > + > > > > > +static enum optab_subtype > > > > > +vect_determine_dot_kind (tree_code code, stmt_vec_info > > > > > +stmt_vinfo) { > > > > > + enum optab_subtype subtype = optab_vector; > > > > > + switch (code) > > > > > + { > > > > > + case DOT_PROD_EXPR: > > > > > + { > > > > > + gassign *stmt = as_a (STMT_VINFO_STMT (stmt_vinfo)); > > > > > + signop rhs1_sign = TYPE_SIGN (TREE_TYPE (gimple_assign_rhs1 > > > > (stmt))); > > > > > + signop rhs2_sign = TYPE_SIGN (TREE_TYPE (gimple_assign_rhs2 > > > > (stmt))); > > > > > + if (rhs1_sign != rhs2_sign) > > > > > + subtype |= optab_unsigned_to_signed; > > > > > + break; > > > > > + } > > > > > + default: > > > > > + break; > > > > > + } > > > > > + > > > > > + return subtype; > > > > > +} > > > > > + > > > > > /* Function vectorizable_reduction. > > > > > > > > > > Check if STMT_INFO performs a reduction operation that can be > > > > vectorized. > > > > > @@ -7189,7 +7216,8 @@ vectorizable_reduction (loop_vec_info > > > > loop_vinfo, > > > > > bool ok = true; > > > > > > > > > > /* 4.1. check support for the operation in the loop */ > > > > > - optab optab = optab_for_tree_code (code, vectype_in, > > optab_vector); > > > > > + enum optab_subtype subtype = vect_determine_dot_kind (code, > > > > stmt_info); > > > > > + optab optab = optab_for_tree_code (code, vectype_in, > > > > > + subtype); > > > > > if (!optab) > > > > > { > > > > > if (dump_enabled_p ()) > > > > > diff --git a/gcc/tree-vect-patterns.c b/gcc/tree-vect-patterns.c > > > > > index > > > > > > > > > > > 441d6cd28c4eaded7abd756164890dbcffd2f3b8..943c001fb13777b4d1513841f > > > > a84 > > > > > 942316846d5e 100644 > > > > > --- a/gcc/tree-vect-patterns.c > > > > > +++ b/gcc/tree-vect-patterns.c > > > > > @@ -201,7 +201,8 @@ vect_get_external_def_edge (vec_info *vinfo, > > > > > tree > > > > > var) static bool vect_supportable_direct_optab_p (vec_info > > > > > *vinfo, tree otype, tree_code code, > > > > > tree itype, tree *vecotype_out, > > > > > - tree *vecitype_out = NULL) > > > > > + tree *vecitype_out = NULL, > > > > > + enum optab_subtype subtype = > > > > optab_default) > > > > > { > > > > > tree vecitype = get_vectype_for_scalar_type (vinfo, itype); > > > > > if (!vecitype) > > > > > @@ -211,7 +212,7 @@ vect_supportable_direct_optab_p (vec_info > > > > > *vinfo, > > > > tree otype, tree_code code, > > > > > if (!vecotype) > > > > > return false; > > > > > > > > > > - optab optab = optab_for_tree_code (code, vecitype, > > > > > optab_default); > > > > > + optab optab = optab_for_tree_code (code, vecitype, subtype); > > > > > if (!optab) > > > > > return false; > > > > > > > > > > @@ -487,14 +488,31 @@ vect_joust_widened_integer (tree type, bool > > > > > shift_p, tree op, } > > > > > > > > > > /* Return true if the common supertype of NEW_TYPE and > > > > *COMMON_TYPE > > > > > - is narrower than type, storing the supertype in *COMMON_TYPE if > > so. > > > > */ > > > > > + is narrower than type, storing the supertype in *COMMON_TYPE if > > so. > > > > > + If ALLOW_SHORT_SIGN_MISMATCH then accept that > > *COMMON_TYPE > > > > and NEW_TYPE > > > > > + may be of different signs but equal precision. */ > > > > > > > > > > static bool > > > > > -vect_joust_widened_type (tree type, tree new_type, tree > > > > *common_type) > > > > > +vect_joust_widened_type (tree type, tree new_type, tree > > > > *common_type, > > > > > + bool allow_short_sign_mismatch = false) > > > > > { > > > > > if (types_compatible_p (*common_type, new_type)) > > > > > return true; > > > > > > > > > > + /* Check if the mismatch is only in the sign and if we have > > > > > + allow_short_sign_mismatch then allow it. */ > > > > > + if (allow_short_sign_mismatch > > > > > + && TYPE_SIGN (*common_type) != TYPE_SIGN (new_type)) > > > > > + { > > > > > + bool sign = TYPE_SIGN (*common_type) == UNSIGNED; > > > > > + tree eq_type > > > > > + = build_nonstandard_integer_type (TYPE_PRECISION (new_type), > > > > > + sign); > > > > > + > > > > > + if (types_compatible_p (*common_type, eq_type)) > > > > > + return true; > > > > > + } > > > > > + > > > > > /* See if *COMMON_TYPE can hold all values of NEW_TYPE. */ > > > > > if ((TYPE_PRECISION (new_type) < TYPE_PRECISION (*common_type)) > > > > > && (TYPE_UNSIGNED (new_type) || !TYPE_UNSIGNED > > > > (*common_type))) > > > > > @@ -532,6 +550,9 @@ vect_joust_widened_type (tree type, tree > > > > new_type, tree *common_type) > > > > > to a type that (a) is narrower than the result of STMT_INFO and > > > > > (b) can hold all leaf operand values. > > > > > > > > > > + If ALLOW_SHORT_SIGN_MISMATCH then allow that the signs of the > > > > operands > > > > > + may differ in signs but not in precision. > > > > > + > > > > > Return 0 if STMT_INFO isn't such a tree, or if no such COMMON_TYPE > > > > > exists. */ > > > > > > > > > > @@ -539,7 +560,8 @@ static unsigned int vect_widened_op_tree > > > > > (vec_info *vinfo, stmt_vec_info stmt_info, tree_code code, > > > > > tree_code widened_code, bool shift_p, > > > > > unsigned int max_nops, > > > > > - vect_unpromoted_value *unprom, tree *common_type) > > > > > + vect_unpromoted_value *unprom, tree *common_type, > > > > > + bool allow_short_sign_mismatch = false) > > > > > { > > > > > /* Check for an integer operation with the right code. */ > > > > > gassign *assign = dyn_cast (stmt_info->stmt); @@ > > > > > -600,7 > > > > > +622,8 @@ vect_widened_op_tree (vec_info *vinfo, stmt_vec_info > > > > stmt_info, tree_code code, > > > > > = vinfo->lookup_def (this_unprom->op); > > > > > nops = vect_widened_op_tree (vinfo, def_stmt_info, code, > > > > > widened_code, shift_p, max_nops, > > > > > - this_unprom, common_type); > > > > > + this_unprom, common_type, > > > > > + allow_short_sign_mismatch); > > > > > if (nops == 0) > > > > > return 0; > > > > > > > > > > @@ -617,7 +640,8 @@ vect_widened_op_tree (vec_info *vinfo, > > > > stmt_vec_info stmt_info, tree_code code, > > > > > if (i == 0) > > > > > *common_type = this_unprom->type; > > > > > else if (!vect_joust_widened_type (type, this_unprom->type, > > > > > - common_type)) > > > > > + common_type, > > > > > + allow_short_sign_mismatch)) > > > > > return 0; > > > > > } > > > > > } > > > > > @@ -888,21 +912,24 @@ vect_reassociating_reduction_p (vec_info > > > > > *vinfo, > > > > > > > > > > Try to find the following pattern: > > > > > > > > > > - type x_t, y_t; > > > > > + type1a x_t > > > > > + type1b y_t; > > > > > TYPE1 prod; > > > > > TYPE2 sum = init; > > > > > loop: > > > > > sum_0 = phi > > > > > S1 x_t = ... > > > > > S2 y_t = ... > > > > > - S3 x_T = (TYPE1) x_t; > > > > > - S4 y_T = (TYPE1) y_t; > > > > > + S3 x_T = (TYPE3) x_t; > > > > > + S4 y_T = (TYPE4) y_t; > > > > > S5 prod = x_T * y_T; > > > > > [S6 prod = (TYPE2) prod; #optional] > > > > > S7 sum_1 = prod + sum_0; > > > > > > > > > > - where 'TYPE1' is exactly double the size of type 'type', and 'TYPE2' is > > the > > > > > - same size of 'TYPE1' or bigger. This is a special case of a reduction > > > > > + where 'TYPE1' is exactly double the size of type 'type1a' and 'type1b', > > > > > + the sign of 'TYPE1' must be one of 'type1a' or 'type1b' but the sign of > > > > > + 'type1a' and 'type1b' can differ. 'TYPE2' is the same size of 'TYPE1' or > > > > > + bigger and must be the same sign. This is a special case of a > > > > > + reduction > > > > > computation. > > > > > > > > > > Input: > > > > > @@ -939,15 +966,16 @@ vect_recog_dot_prod_pattern (vec_info > > > > > *vinfo, > > > > > > > > > > /* Look for the following pattern > > > > > DX = (TYPE1) X; > > > > > - DY = (TYPE1) Y; > > > > > + DY = (TYPE2) Y; > > > > > DPROD = DX * DY; > > > > > - DDPROD = (TYPE2) DPROD; > > > > > + DDPROD = (TYPE3) DPROD; > > > > > sum_1 = DDPROD + sum_0; > > > > > In which > > > > > - DX is double the size of X > > > > > - DY is double the size of Y > > > > > - DX, DY, DPROD all have the same type but the sign > > > > > - between DX, DY and DPROD can differ. > > > > > + between DX, DY and DPROD can differ. The sign of DPROD > > > > > + is one of the signs of DX or DY. > > > > > - sum is the same size of DPROD or bigger > > > > > - sum has been recognized as a reduction variable. > > > > > > > > > > @@ -986,14 +1014,41 @@ vect_recog_dot_prod_pattern (vec_info > > *vinfo, > > > > > inside the loop (in case we are analyzing an outer-loop). */ > > > > > vect_unpromoted_value unprom0[2]; > > > > > if (!vect_widened_op_tree (vinfo, mult_vinfo, MULT_EXPR, > > > > WIDEN_MULT_EXPR, > > > > > - false, 2, unprom0, &half_type)) > > > > > + false, 2, unprom0, &half_type, true)) > > > > > return NULL; > > > > > > > > > > + /* Check to see if there is a sign change happening in the > > > > > + operands of > > > > the > > > > > + multiplication and pick the appropriate optab subtype. */ > > > > > + enum optab_subtype subtype; > > > > > + tree rhs_type1 = unprom0[0].type; > > > > > + tree rhs_type2 = unprom0[1].type; > > > > > + if (TYPE_SIGN (rhs_type1) == TYPE_SIGN (rhs_type2)) > > > > > + subtype = optab_default; > > > > > + else if (TYPE_SIGN (rhs_type1) == SIGNED > > > > > + && TYPE_SIGN (rhs_type2) == UNSIGNED) > > > > > + subtype = optab_signed_to_unsigned; > > > > > + else if (TYPE_SIGN (rhs_type1) == UNSIGNED > > > > > + && TYPE_SIGN (rhs_type2) == SIGNED) > > > > > + subtype = optab_unsigned_to_signed; > > > > > + else > > > > > + gcc_unreachable (); > > > > > + > > > > > + /* If we have a sign changing dot product we need to check that the > > > > > + promoted type if unsigned has at least the same precision as the > > final > > > > > + type of the dot-product. */ > > > > > + if (subtype != optab_default) > > > > > + { > > > > > + tree mult_type = TREE_TYPE (unprom_mult.op); > > > > > + if (TYPE_SIGN (mult_type) == UNSIGNED > > > > > + && TYPE_PRECISION (mult_type) < TYPE_PRECISION (type)) > > > > > + return NULL; > > > > > + } > > > > > + > > > > > vect_pattern_detected ("vect_recog_dot_prod_pattern", > > > > > last_stmt); > > > > > > > > > > tree half_vectype; > > > > > if (!vect_supportable_direct_optab_p (vinfo, type, > > > > > DOT_PROD_EXPR, > > > > half_type, > > > > > - type_out, &half_vectype)) > > > > > + type_out, &half_vectype, subtype)) > > > > > return NULL; > > > > > > > > > > /* Get the inputs in the appropriate types. */ @@ -1002,8 > > > > > +1057,22 @@ vect_recog_dot_prod_pattern (vec_info *vinfo, > > > > > unprom0, half_vectype); > > > > > > > > > > var = vect_recog_temp_ssa_var (type, NULL); > > > > > + > > > > > + /* If we have a sign changing dot-product the dot-product itself does > > any > > > > > + sign conversions, so consume the type and use the unpromoted > > > > > + types. */ tree mult_arg1, mult_arg2; if (subtype == > > > > > + optab_default) > > > > > + { > > > > > + mult_arg1 = mult_oprnd[0]; > > > > > + mult_arg2 = mult_oprnd[1]; > > > > > + } > > > > > + else > > > > > + { > > > > > + mult_arg1 = unprom0[0].op; > > > > > + mult_arg2 = unprom0[1].op; > > > > > + } > > > > > pattern_stmt = gimple_build_assign (var, DOT_PROD_EXPR, > > > > > - mult_oprnd[0], mult_oprnd[1], oprnd1); > > > > > + mult_arg1, mult_arg2, oprnd1); > > > > > > > > > > return pattern_stmt; > > > > > } > > > > > > > > > > > > > > > > > > > > > > > -- > > > > Richard Biener > > > > SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 > > > > Nuernberg, Germany; GF: Felix Imendörffer; HRB 36809 (AG Nuernberg) > > > > > > > -- > > Richard Biener > > SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 > > Nuernberg, Germany; GF: Felix Imendörffer; HRB 36809 (AG Nuernberg) > -- Richard Biener SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany; GF: Felix Imendörffer; HRB 36809 (AG Nuernberg)