similar to: [LLVMdev] type legalizer promoting BUILD_VECTORs

On Mon, Feb 2, 2009 at 11:31 AM, Bob Wilson <bob.wilson at apple.com> wrote: > LLVM's type legalizer is changing the types of BUILD_VECTORs in a way > that seems wrong to me, but I'm not sure if this is a bug or if some > targets may be relying on it. > > On a 32-bit target, the default action for legalizing i8 and i16 types > is to promote them. This isn't

Hi Bob, > LLVM's type legalizer is changing the types of BUILD_VECTORs in a way > that seems wrong to me, but I'm not sure if this is a bug or if some > targets may be relying on it. > > On a 32-bit target, the default action for legalizing i8 and i16 types > is to promote them. If you then have a BUILD_VECTOR to construct a > legal vector type composed of

On Feb 2, 2009, at 1:51 PM, Eli Friedman wrote: > On Mon, Feb 2, 2009 at 11:31 AM, Bob Wilson <bob.wilson at apple.com> > wrote: >> LLVM's type legalizer is changing the types of BUILD_VECTORs in a way >> that seems wrong to me, but I'm not sure if this is a bug or if some >> targets may be relying on it. >> >> On a 32-bit target, the default

(Resend, since it didn't seem to reach the mailing list the first time) Hi Bob, > LLVM's type legalizer is changing the types of BUILD_VECTORs in a way > that seems wrong to me, but I'm not sure if this is a bug or if some > targets may be relying on it. > > On a 32-bit target, the default action for legalizing i8 and i16 types > is to promote them. If you

On Feb 2, 2009, at 1:22 PM, Duncan Sands wrote: > another way this could be done is to say that the operands of a > BUILD_VECTOR don't have to have the same type as the element type > of the built vector. Then when the type legalizer sees a > v4i16 = BUILD_VECTOR(i16, i16, i16, i16) it can turn this into a > v4i16 = BUILD_VECTOR(i32, i32, i32, i32) and it will be happy >

Hi Dale, I think Bob is right: the type legalizer shouldn't be turning v16i8 into v16i32, what should happen is that the return type of the BUILD_VECTOR continues to be v16i8, but the type of the operands changes to i32, so you end up with a BUILD_VECTOR that takes 16 lots of i32, and produces a v16i8. The target then has all the info it needs to produce the best code, but needs to be careful

I have two patterns in tablegen that do look like the exact same thing: Pat 1) def MOV_v4i16 : ILFormat<IL_OP_MOV, (outs GPRV4I16:$dst), (ins i16imm:$val), asm, [(set GPRV4I16:$dst, (build_vector (i16 imm:$val)))]>; Pat 2) def v4i16imm : Operand<v4i16>; def MOV_v4i16 : ILFormat<IL_OP_MOV, (outs GPRV4I16:$dst), (ins v4i16imm:$val), asm, [(set

On Nov 9, 2009, at 6:11 PM, Dale Johannesen wrote: > PPC Altivec supports vector type v16i8 (and others) where the element > type is not legal (in llvm's implementation). When we have a > BUILD_VECTOR of these types with constant elements, LegalizeTypes > first promotes the element types to i32, then builds a constant pool > entry of type v16i32. This is wrong. I can

PPC Altivec supports vector type v16i8 (and others) where the element type is not legal (in llvm's implementation). When we have a BUILD_VECTOR of these types with constant elements, LegalizeTypes first promotes the element types to i32, then builds a constant pool entry of type v16i32. This is wrong. I can fix it by truncating the elements back to i8 in ExpandBUILD_VECTOR. Does

On Oct 26, 2008, at 1:03 AM, Duncan Sands wrote: > Hi all, I plan to turn on the new type legalization infrastructure > "LegalizeTypes" by default tomorrow. This is a redesign/ > reimplementation > of the logic currently in LegalizeDAG that turns (for example) 64 bit > arithmetic on a 32 bit machine into a series of 32 bit operations. > As well > as being a

Hi Krzysztof, Sure, please see below. DAG.dump.() before and after, annotated with what I believe the DAG means. I've spent some time debugging the method but it's proving difficult to determine where the logic is misfiring. Disabling the entire combine causes a lot of failing x86-64 tests - I may have to learn an upstream vector ISA to make progress on this. Thank you >From your

Hi all, I plan to turn on the new type legalization infrastructure "LegalizeTypes" by default tomorrow. This is a redesign/reimplementation of the logic currently in LegalizeDAG that turns (for example) 64 bit arithmetic on a 32 bit machine into a series of 32 bit operations. As well as being a cleaner design, it also supports code generation for arbitrary precision integers such as

Hrmm.... PromoteVectorOp doesn't seem to follow this at all. http://llvm.org/svn/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp SDValue VectorLegalizer::PromoteVectorOp(SDValue Op) { // Vector "promotion" is basically just bitcasting and doing the operation // in a different type. For example, x86 promotes ISD::AND on v2i32 to // v1i64. EVT VT =

Hi all, I have a backend for an in house architecture, and would like to start working on support for vector datatypes and intrinsics. As I starter I would like to have vector code scalarized, as is done, e.g., for the Mips backend. However, I cannot find a way to force the instruction selector or type legalizer to scalarize the vectors (i.e., vector types and vector ops). Can anyone help me out?

v4i8 itself is a legal type, just not on the 'AND' operation. So there seems to be multiple problems here. 1) PromoteVectorOp doesn't handle the case where the types are not the same size, this occurs because #2 2) getTypeToPromoteTo doesn't actual check to see if the type it should promote to makes any sense. 3) PromoteVectorOp also doesn't handle the case where

I don't know how your target architecture looks like, but I suspect that <4 x i8> should not be legalized to <1 x i32>. I think that what you are seeing is that <4 x i8> is first split into <2 x i8>, and later promoted to <2 x i32>. At the moment different targets can only affect type-legalization by declaring different legal types. A number of us discussed the

Notice that PromoteVectorOp is called after the type legalization legalized all of the types in the program. It legalizes the *operations*, not the types. So, you should only see legal types (Legal types are types that fit into your registers). So, if your target has v2i32, I suspect that v4i8 is an illegal because it has a different size. -----Original Message----- From: Villmow, Micah

Hi Dale, > PPC Altivec supports vector type v16i8 (and others) where the element > type is not legal (in llvm's implementation). When we have a > BUILD_VECTOR of these types with constant elements, LegalizeTypes first > promotes the element types to i32, then builds a constant pool entry of > type v16i32. are you sure? I would expect it to build v4i32. Ciao, Duncan.

On Nov 9, 2009, at 6:33 PM, Duncan Sands wrote: > Hi Dale, > >> PPC Altivec supports vector type v16i8 (and others) where the >> element type is not legal (in llvm's implementation). When we have >> a BUILD_VECTOR of these types with constant elements, LegalizeTypes >> first promotes the element types to i32, then builds a constant >> pool entry of

I have the following selection DAG: SelectionDAG has 9 nodes: t0: ch = EntryToken t2: i64,ch = CopyFromReg t0, Register:i64 %vreg0 t16: i32,ch = load<LD1[%ptr](tbaa=<0x10023c9f448>), anyext from i8> t0, t2, undef:i64 t15: v16i8 = BUILD_VECTOR t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16, t16 t11: ch,glue = CopyToReg t0, Register:v16i8 %V2, t15