We could easily convert it to SUB dst, -src1, -imm. Thus we can avoid one LOADI instruction eventually.
Signed-off-by: Zhigang Gong <[email protected]> --- backend/src/backend/gen_insn_selection.cpp | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) diff --git a/backend/src/backend/gen_insn_selection.cpp b/backend/src/backend/gen_insn_selection.cpp index adf523c..a554ee9 100644 --- a/backend/src/backend/gen_insn_selection.cpp +++ b/backend/src/backend/gen_insn_selection.cpp @@ -1665,18 +1665,19 @@ namespace gbe return false; } - GenRegister getRegisterFromImmediate(ir::Immediate imm) + GenRegister getRegisterFromImmediate(ir::Immediate imm, bool negate = false) { using namespace ir; + int sign = negate ? -1 : 1; switch (imm.type) { - case TYPE_U32: return GenRegister::immud(imm.data.u32); - case TYPE_S32: return GenRegister::immd(imm.data.s32); - case TYPE_FLOAT: return GenRegister::immf(imm.data.f32); - case TYPE_U16: return GenRegister::immuw(imm.data.u16); - case TYPE_S16: return GenRegister::immw(imm.data.s16); - case TYPE_U8: return GenRegister::immuw(imm.data.u8); - case TYPE_S8: return GenRegister::immw(imm.data.s8); - case TYPE_DOUBLE: return GenRegister::immdf(imm.data.f64); + case TYPE_U32: return GenRegister::immud(imm.data.u32 * sign); + case TYPE_S32: return GenRegister::immd(imm.data.s32 * sign); + case TYPE_FLOAT: return GenRegister::immf(imm.data.f32 * sign); + case TYPE_U16: return GenRegister::immuw(imm.data.u16 * sign); + case TYPE_S16: return GenRegister::immw(imm.data.s16 * sign); + case TYPE_U8: return GenRegister::immuw(imm.data.u8 * sign); + case TYPE_S8: return GenRegister::immw(imm.data.s8 * sign); + case TYPE_DOUBLE: return GenRegister::immdf(imm.data.f64 * sign); case TYPE_BOOL: return GenRegister::immuw(-imm.data.b); //return 0xffff when true default: NOT_SUPPORTED; return GenRegister::immuw(0); } @@ -1969,11 +1970,14 @@ namespace gbe if (dag0) dag0->isRoot = 1; } // Left source cannot be immediate but it is OK if we can commute - else if (OCL_OPTIMIZE_IMMEDIATE && dag0 != NULL && insn.commutes() && dag0->insn.getOpcode() == OP_LOADI && - canGetRegisterFromImmediate(dag0->insn) && type != TYPE_BOOL) { + else if (OCL_OPTIMIZE_IMMEDIATE && dag0 != NULL && + (insn.commutes() || insn.getOpcode() == OP_SUB) && + dag0->insn.getOpcode() == OP_LOADI && canGetRegisterFromImmediate(dag0->insn) && + type != TYPE_BOOL) { const auto &childInsn = cast<LoadImmInstruction>(dag0->insn); - src0 = sel.selReg(insn.getSrc(1), type); - src1 = getRegisterFromImmediate(childInsn.getImmediate()); + src0 = insn.getOpcode() != OP_SUB ? + sel.selReg(insn.getSrc(1), type) : GenRegister::negate(sel.selReg(insn.getSrc(1), type)); + src1 = getRegisterFromImmediate(childInsn.getImmediate(), insn.getOpcode() == OP_SUB); if (dag1) dag1->isRoot = 1; } // Just grab the two sources -- 1.8.3.2 _______________________________________________ Beignet mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/beignet
