That's the tricky part. And as I know, i1 1 is actually -1 thus is less than 0. And you can see it is consistent when you extent i1 to i16 which is a signed extend.
> -----Original Message----- > From: Yang, Rong R > Sent: Monday, March 2, 2015 4:11 PM > To: Gong, Zhigang; [email protected] > Cc: Gong, Zhigang > Subject: RE: [Beignet] [PATCH] GBE: support compare two bool variables. > > For the instruction: > %Pivot = icmp slt i1 %trunc49, false > > And slt is: interprets the operands as signed values and yields true if op1 > is less > than op2. > > But %trunc49 only has 1 bit, How to interprets %trunc49 as signed values? Only > signed bit? > > When %trunc49's value is true, what should be this instruction's result? > > > -----Original Message----- > > From: Beignet [mailto:[email protected]] On Behalf > > Of Zhigang Gong > > Sent: Monday, March 2, 2015 12:29 > > To: [email protected] > > Cc: Gong, Zhigang > > Subject: [Beignet] [PATCH] GBE: support compare two bool variables. > > > > LLVM 3.6 may generate the following instructions: > > > > %Pivot = icmp slt i1 %trunc49, false > > > > when do siwth lowering pass. > > To support it we must use GEN_TYPE_W to represent B rather than > > GEN_TYPE_UW and we also need to remove the corresponding assertions. > > > > Signed-off-by: Zhigang Gong <[email protected]> > > --- > > backend/src/backend/gen_insn_selection.cpp | 4 ++-- > > backend/src/ir/instruction.cpp | 1 - > > backend/src/llvm/llvm_gen_backend.cpp | 2 -- > > 3 files changed, 2 insertions(+), 5 deletions(-) > > > > diff --git a/backend/src/backend/gen_insn_selection.cpp > > b/backend/src/backend/gen_insn_selection.cpp > > index 106ea82..d100f80 100644 > > --- a/backend/src/backend/gen_insn_selection.cpp > > +++ b/backend/src/backend/gen_insn_selection.cpp > > @@ -115,7 +115,7 @@ namespace gbe > > uint32_t getGenType(ir::Type type) { > > using namespace ir; > > switch (type) { > > - case TYPE_BOOL: return GEN_TYPE_UW; > > + case TYPE_BOOL: return GEN_TYPE_W; > > case TYPE_S8: return GEN_TYPE_B; > > case TYPE_U8: return GEN_TYPE_UB; > > case TYPE_S16: return GEN_TYPE_W; @@ -1956,7 +1956,7 @@ > > namespace gbe > > case TYPE_U8: return > GenRegister::immuw(imm.getIntegerValue() > > * sign); > > case TYPE_S8: return > > GenRegister::immw((int8_t)imm.getIntegerValue() > > * sign); > > case TYPE_DOUBLE: return > > GenRegister::immdf(imm.getDoubleValue() * sign); > > - case TYPE_BOOL: return > GenRegister::immuw(-imm.getIntegerValue()); > > //return 0xffff when true > > + case TYPE_BOOL: return > GenRegister::immw((imm.getIntegerValue() > > + == 0) ? 0 : -1); //return 0xffff when true > > default: NOT_SUPPORTED; return GenRegister::immuw(0); > > } > > } > > diff --git a/backend/src/ir/instruction.cpp > > b/backend/src/ir/instruction.cpp index 1e1b040..a2bc875 100644 > > --- a/backend/src/ir/instruction.cpp > > +++ b/backend/src/ir/instruction.cpp > > @@ -889,7 +889,6 @@ namespace ir { > > for (uint32_t srcID = 0; srcID < 2; ++srcID) > > if (UNLIKELY(checkRegisterData(family, src[srcID], fn, whyNot) == > false)) > > return false; > > - CHECK_TYPE(this->type, allButBool); > > return true; > > } > > > > diff --git a/backend/src/llvm/llvm_gen_backend.cpp > > b/backend/src/llvm/llvm_gen_backend.cpp > > index 43b50e7..238f572 100644 > > --- a/backend/src/llvm/llvm_gen_backend.cpp > > +++ b/backend/src/llvm/llvm_gen_backend.cpp > > @@ -2151,8 +2151,6 @@ namespace gbe > > } > > > > void GenWriter::emitICmpInst(ICmpInst &I) { > > - GBE_ASSERT(I.getOperand(0)->getType() != > > Type::getInt1Ty(I.getContext())); > > - > > // Get the element type and the number of elements > > Type *operandType = I.getOperand(0)->getType(); > > const ir::Type type = getType(ctx, operandType); > > -- > > 1.9.1 > > > > _______________________________________________ > > Beignet mailing list > > [email protected] > > http://lists.freedesktop.org/mailman/listinfo/beignet _______________________________________________ Beignet mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/beignet
