From c2b33d0be998bf539953f1dad0aa0d1cc8d9d069 Mon Sep 17 00:00:00 2001 From: Taylor Simpson Date: Mon, 6 Mar 2023 18:58:28 -0800 Subject: Hexagon (target/hexagon) Improve code gen for predicated HVX instructions The following improvements are made for predicated HVX instructions During gen_commit_hvx, unconditionally move the "new" value into the dest Don't set slot_cancelled Remove runtime bookkeeping of which registers were updated Reduce the cases where gen_log_vreg_write[_pair] is called It's only needed for special operands VxxV and VyV Remove gen_log_qreg_write Signed-off-by: Taylor Simpson Reviewed-by: Anton Johansson Message-Id: <20230307025828.1612809-15-tsimpson@quicinc.com> --- target/hexagon/README | 21 +++++---------------- 1 file changed, 5 insertions(+), 16 deletions(-) (limited to 'target/hexagon/README') diff --git a/target/hexagon/README b/target/hexagon/README index 365606f..ebafc78 100644 --- a/target/hexagon/README +++ b/target/hexagon/README @@ -136,12 +136,9 @@ For HVX vectors, the generator behaves slightly differently. The wide vectors won't fit in a TCGv or TCGv_i64, so we pass TCGv_ptr variables to pass the address to helper functions. Here's an example for an HVX vector-add-word istruction. - static void generate_V6_vaddw( - CPUHexagonState *env, - DisasContext *ctx, - Insn *insn, - Packet *pkt) + static void generate_V6_vaddw(DisasContext *ctx) { + Insn *insn __attribute__((unused)) = ctx->insn; const int VdN = insn->regno[0]; const intptr_t VdV_off = ctx_future_vreg_off(ctx, VdN, 1, true); @@ -157,9 +154,7 @@ istruction. TCGv_ptr VvV = tcg_temp_new_ptr(); tcg_gen_addi_ptr(VuV, cpu_env, VuV_off); tcg_gen_addi_ptr(VvV, cpu_env, VvV_off); - TCGv slot = tcg_constant_tl(insn->slot); - gen_helper_V6_vaddw(cpu_env, VdV, VuV, VvV, slot); - gen_log_vreg_write(ctx, VdV_off, VdN, EXT_DFL, insn->slot, false); + gen_helper_V6_vaddw(cpu_env, VdV, VuV, VvV); } Notice that we also generate a variable named _off for each operand of @@ -172,12 +167,9 @@ functions from tcg-op-gvec.h. Here's the override for this instruction. Finally, we notice that the override doesn't use the TCGv_ptr variables, so we don't generate them when an override is present. Here is what we generate when the override is present. - static void generate_V6_vaddw( - CPUHexagonState *env, - DisasContext *ctx, - Insn *insn, - Packet *pkt) + static void generate_V6_vaddw(DisasContext *ctx) { + Insn *insn __attribute__((unused)) = ctx->insn; const int VdN = insn->regno[0]; const intptr_t VdV_off = ctx_future_vreg_off(ctx, VdN, 1, true); @@ -188,7 +180,6 @@ when the override is present. const intptr_t VvV_off = vreg_src_off(ctx, VvN); fGEN_TCG_V6_vaddw({ fHIDE(int i;) fVFOREACH(32, i) { VdV.w[i] = VuV.w[i] + VvV.w[i] ; } }); - gen_log_vreg_write(ctx, VdV_off, VdN, EXT_DFL, insn->slot, false); } We also generate an analyze_ function for each instruction. Currently, @@ -281,10 +272,8 @@ For Hexagon Vector eXtensions (HVX), the following fields are used VRegs Vector registers future_VRegs Registers to be stored during packet commit tmp_VRegs Temporary registers *not* stored during commit - VRegs_updated Mask of predicated vector writes QRegs Q (vector predicate) registers future_QRegs Registers to be stored during packet commit - QRegs_updated Mask of predicated vector writes *** Debugging *** -- cgit v1.1