similar to: [LLVMdev] Cleanups in ROTL/ROTR DAG combiner code

Hi all, While I test "clang-tests/gcc-4_2-testsuite/src/gcc.c-torture/execute/20020226-1.c", I faced something wrong with "DAGCombiner::MatchRotate" function. This function tries to consume some patterns and generate "ROTL" or "ROTR" dag node as following comments: "DAGCombier::MatchRotate" function in DAGCombiner.cpp Pattern1 // fold (or

I can get clang/llvm to emit a rotate instruction on x86-64 when compiling C by just using -Os and the rotate from Hacker's Delight i.e., ====== #include <stdlib.h> #include <stdint.h> uint32_t ror(uint32_t input, size_t rot_bits) { return (input >> rot_bits) | (input << ((sizeof(input) << 3) - rot_bits)); } ====== Then compile with (assuming you are on OS

*NOTE* IIRC compiling this with -O0 on x86-64 can yield the wrong result since clang will emit shifts and on intel shifts are mod the register size: ===== .section __TEXT,__text,regular,pure_instructions .globl _ror .align 4, 0x90 _ror: ## @ror .cfi_startproc ## BB#0: pushq %rbp Ltmp2: .cfi_def_cfa_offset 16 Ltmp3: .cfi_offset %rbp, -16 movq %rsp, %rbp

Nice! Clever compiler.. On 07/28/2012 08:55 PM, Michael Gottesman wrote: > I can get clang/llvm to emit a rotate instruction on x86-64 when compiling C by just using -Os and the rotate from Hacker's Delight i.e., > > ====== > #include<stdlib.h> > #include<stdint.h> > > uint32_t ror(uint32_t input, size_t rot_bits) > { > return (input>>

--- On Tue, 2/3/09, Bill Wendling <isanbard at gmail.com> wrote: > From: Bill Wendling <isanbard at gmail.com> > Subject: Re: [LLVMdev] rol/ror llvm instruction set > To: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > Cc: kasra_n500 at yahoo.com > Date: Tuesday, February 3, 2009, 2:52 PM > On Tue, Feb 3, 2009 at 2:45 PM, Dale Johannesen

I've done a decent size update of the OpenSSH portable from the upstream tree. There is an AES upgrade that needs to take place, but I need people to test and tell me what endedness changes need to be applied (if any). Attached is the patch. It is geared towards the latter snapshots..Unsure how it will patch (if at all) against 2.9pX series. Thanks. - Ben "This is dark day in

On Wed, May 20, 2009 at 1:19 PM, Eli Friedman <eli.friedman at gmail.com> wrote: > Per subject, this patch adding an additional pass to handle vector > operations; the idea is that this allows removing the code from > LegalizeDAG that handles illegal types, which should be a significant > simplification.  There are still some issues with this patch, but does > the approach

On Tue, Feb 3, 2009 at 2:45 PM, Dale Johannesen <dalej at apple.com> wrote: > > On Feb 3, 2009, at 2:35 PMPST, Mike Stump wrote: > >> On Feb 3, 2009, at 2:28 PM, Kasra wrote: >>> I was looking around the LLVM instruction set and I failed to find >>> ROL and ROR instructions. Is there any plans on adding these >>> instructions to LLVM? >>

Well, we like the operator because it maps cleanly to Fortran's ISHFTC intrinsic. There must also be other compilers out there, maybe catering to cryptos, that have their own intrinsic for circular shift in other languages. It seems wasteful for an optimizer to break apart an intrinsic into its elemental pieces in order for LLVM to put them back together. This was done in our compiler for some

in C or C++, how can I get clang/llvm to try and do a "rotate". (want to test this code in the mips16 port) i.e. emit rotr node. tia. reed

Per subject, this patch adding an additional pass to handle vector operations; the idea is that this allows removing the code from LegalizeDAG that handles illegal types, which should be a significant simplification. There are still some issues with this patch, but does the approach look sane? -Eli -------------- next part -------------- Index: lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp

On Wed, May 20, 2009 at 5:26 PM, Eli Friedman <eli.friedman at gmail.com> wrote: > On Wed, May 20, 2009 at 4:55 PM, Dan Gohman <gohman at apple.com> wrote: >> Can you explain why you chose the approach of using a new pass? >> I pictured removing LegalizeDAG's type legalization code would >> mostly consist of finding all the places that use TLI.getTypeAction