From 59a71b4c5b4ef2ef6425b9e21c972dd5bf450275 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Sat, 15 Oct 2016 11:41:29 -0500 Subject: [PATCH] target-arm: Use new deposit and extract ops Use the new primitives for UBFX and SBFX. Signed-off-by: Richard Henderson --- target/arm/translate-a64.c | 81 ++++++++++++++------------------------ target/arm/translate.c | 37 ++++------------- 2 files changed, 37 insertions(+), 81 deletions(-) diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index f673d939e1ad..a59c90c9ad81 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -3216,67 +3216,44 @@ static void disas_bitfield(DisasContext *s, uint32_t insn) low 32-bits anyway. */ tcg_tmp = read_cpu_reg(s, rn, 1); - /* Recognize the common aliases. */ - if (opc == 0) { /* SBFM */ - if (ri == 0) { - if (si == 7) { /* SXTB */ - tcg_gen_ext8s_i64(tcg_rd, tcg_tmp); - goto done; - } else if (si == 15) { /* SXTH */ - tcg_gen_ext16s_i64(tcg_rd, tcg_tmp); - goto done; - } else if (si == 31) { /* SXTW */ - tcg_gen_ext32s_i64(tcg_rd, tcg_tmp); - goto done; - } - } - if (si == 63 || (si == 31 && ri <= si)) { /* ASR */ - if (si == 31) { - tcg_gen_ext32s_i64(tcg_tmp, tcg_tmp); - } - tcg_gen_sari_i64(tcg_rd, tcg_tmp, ri); + /* Recognize simple(r) extractions. */ + if (si <= ri) { + /* Wd = Wn */ + len = (si - ri) + 1; + if (opc == 0) { /* SBFM: ASR, SBFX, SXTB, SXTH, SXTW */ + tcg_gen_sextract_i64(tcg_rd, tcg_tmp, ri, len); goto done; - } - } else if (opc == 2) { /* UBFM */ - if (ri == 0) { /* UXTB, UXTH, plus non-canonical AND */ - tcg_gen_andi_i64(tcg_rd, tcg_tmp, bitmask64(si + 1)); + } else if (opc == 2) { /* UBFM: UBFX, LSR, UXTB, UXTH */ + tcg_gen_extract_i64(tcg_rd, tcg_tmp, ri, len); return; } - if (si == 63 || (si == 31 && ri <= si)) { /* LSR */ - if (si == 31) { - tcg_gen_ext32u_i64(tcg_tmp, tcg_tmp); - } - tcg_gen_shri_i64(tcg_rd, tcg_tmp, ri); - return; - } - if (si + 1 == ri && si != bitsize - 1) { /* LSL */ - int shift = bitsize - 1 - si; - tcg_gen_shli_i64(tcg_rd, tcg_tmp, shift); - goto done; - } - } - - if (opc != 1) { /* SBFM or UBFM */ - tcg_gen_movi_i64(tcg_rd, 0); - } - - /* do the bit move operation */ - if (si >= ri) { - /* Wd = Wn */ - tcg_gen_shri_i64(tcg_tmp, tcg_tmp, ri); + /* opc == 1, BXFIL fall through to deposit */ + tcg_gen_extract_i64(tcg_tmp, tcg_tmp, ri, len); pos = 0; - len = (si - ri) + 1; } else { - /* Wd<32+s-r,32-r> = Wn */ - pos = bitsize - ri; + /* Handle the ri > si case with a deposit + * Wd<32+s-r,32-r> = Wn + */ len = si + 1; + pos = (bitsize - ri) & (bitsize - 1); } - tcg_gen_deposit_i64(tcg_rd, tcg_rd, tcg_tmp, pos, len); + if (opc == 0 && len < ri) { + /* SBFM: sign extend the destination field from len to fill + the balance of the word. Let the deposit below insert all + of those sign bits. */ + tcg_gen_sextract_i64(tcg_tmp, tcg_tmp, 0, len); + len = ri; + } - if (opc == 0) { /* SBFM - sign extend the destination field */ - tcg_gen_shli_i64(tcg_rd, tcg_rd, 64 - (pos + len)); - tcg_gen_sari_i64(tcg_rd, tcg_rd, 64 - (pos + len)); + if (opc == 1) { /* BFM, BXFIL */ + tcg_gen_deposit_i64(tcg_rd, tcg_rd, tcg_tmp, pos, len); + } else { + /* SBFM or UBFM: We start with zero, and we haven't modified + any bits outside bitsize, therefore the zero-extension + below is unneeded. */ + tcg_gen_deposit_z_i64(tcg_rd, tcg_tmp, pos, len); + return; } done: diff --git a/target/arm/translate.c b/target/arm/translate.c index 0ad9070b45aa..08da9aceb622 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -288,29 +288,6 @@ static void gen_revsh(TCGv_i32 var) tcg_gen_ext16s_i32(var, var); } -/* Unsigned bitfield extract. */ -static void gen_ubfx(TCGv_i32 var, int shift, uint32_t mask) -{ - if (shift) - tcg_gen_shri_i32(var, var, shift); - tcg_gen_andi_i32(var, var, mask); -} - -/* Signed bitfield extract. */ -static void gen_sbfx(TCGv_i32 var, int shift, int width) -{ - uint32_t signbit; - - if (shift) - tcg_gen_sari_i32(var, var, shift); - if (shift + width < 32) { - signbit = 1u << (width - 1); - tcg_gen_andi_i32(var, var, (1u << width) - 1); - tcg_gen_xori_i32(var, var, signbit); - tcg_gen_subi_i32(var, var, signbit); - } -} - /* Return (b << 32) + a. Mark inputs as dead */ static TCGv_i64 gen_addq_msw(TCGv_i64 a, TCGv_i32 b) { @@ -9178,9 +9155,9 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn) goto illegal_op; if (i < 32) { if (op1 & 0x20) { - gen_ubfx(tmp, shift, (1u << i) - 1); + tcg_gen_extract_i32(tmp, tmp, shift, i); } else { - gen_sbfx(tmp, shift, i); + tcg_gen_sextract_i32(tmp, tmp, shift, i); } } store_reg(s, rd, tmp); @@ -10497,15 +10474,17 @@ static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw imm++; if (shift + imm > 32) goto illegal_op; - if (imm < 32) - gen_sbfx(tmp, shift, imm); + if (imm < 32) { + tcg_gen_sextract_i32(tmp, tmp, shift, imm); + } break; case 6: /* Unsigned bitfield extract. */ imm++; if (shift + imm > 32) goto illegal_op; - if (imm < 32) - gen_ubfx(tmp, shift, (1u << imm) - 1); + if (imm < 32) { + tcg_gen_extract_i32(tmp, tmp, shift, imm); + } break; case 3: /* Bitfield insert/clear. */ if (imm < shift)