target/loongarch: Add branch instruction translation

This includes:
- BEQ, BNE, BLT[U], BGE[U]
- BEQZ, BNEZ
- B
- BL
- JIRL
- BCEQZ, BCNEZ

Signed-off-by: Song Gao <gaosong@loongson.cn>
Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220606124333.2060567-16-yangxiaojuan@loongson.cn>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 83 insertions, 0 deletions

diff --git a/target/loongarch/insn_trans/trans_branch.c.inc b/target/loongarch/insn_trans/trans_branch.c.inc
new file mode 100644
index 0000000..65dbdff
--- /dev/null
+++ b/target/loongarch/insn_trans/trans_branch.c.inc
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2021 Loongson Technology Corporation Limited
+ */
+
+static bool trans_b(DisasContext *ctx, arg_b *a)
+{
+    gen_goto_tb(ctx, 0, ctx->base.pc_next + a->offs);
+    ctx->base.is_jmp = DISAS_NORETURN;
+    return true;
+}
+
+static bool trans_bl(DisasContext *ctx, arg_bl *a)
+{
+    tcg_gen_movi_tl(cpu_gpr[1], ctx->base.pc_next + 4);
+    gen_goto_tb(ctx, 0, ctx->base.pc_next + a->offs);
+    ctx->base.is_jmp = DISAS_NORETURN;
+    return true;
+}
+
+static bool trans_jirl(DisasContext *ctx, arg_jirl *a)
+{
+    TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
+    TCGv src1 = gpr_src(ctx, a->rj, EXT_NONE);
+
+    tcg_gen_addi_tl(cpu_pc, src1, a->offs);
+    tcg_gen_movi_tl(dest, ctx->base.pc_next + 4);
+    gen_set_gpr(a->rd, dest, EXT_NONE);
+    tcg_gen_lookup_and_goto_ptr();
+    ctx->base.is_jmp = DISAS_NORETURN;
+    return true;
+}
+
+static void gen_bc(DisasContext *ctx, TCGv src1, TCGv src2,
+                   target_long offs, TCGCond cond)
+{
+    TCGLabel *l = gen_new_label();
+    tcg_gen_brcond_tl(cond, src1, src2, l);
+    gen_goto_tb(ctx, 1, ctx->base.pc_next + 4);
+    gen_set_label(l);
+    gen_goto_tb(ctx, 0, ctx->base.pc_next + offs);
+    ctx->base.is_jmp = DISAS_NORETURN;
+}
+
+static bool gen_rr_bc(DisasContext *ctx, arg_rr_offs *a, TCGCond cond)
+{
+    TCGv src1 = gpr_src(ctx, a->rj, EXT_NONE);
+    TCGv src2 = gpr_src(ctx, a->rd, EXT_NONE);
+
+    gen_bc(ctx, src1, src2, a->offs, cond);
+    return true;
+}
+
+static bool gen_rz_bc(DisasContext *ctx, arg_r_offs *a, TCGCond cond)
+{
+    TCGv src1 = gpr_src(ctx, a->rj, EXT_NONE);
+    TCGv src2 = tcg_constant_tl(0);
+
+    gen_bc(ctx, src1, src2, a->offs, cond);
+    return true;
+}
+
+static bool gen_cz_bc(DisasContext *ctx, arg_c_offs *a, TCGCond cond)
+{
+    TCGv src1 = tcg_temp_new();
+    TCGv src2 = tcg_constant_tl(0);
+
+    tcg_gen_ld8u_tl(src1, cpu_env,
+                    offsetof(CPULoongArchState, cf[a->cj]));
+    gen_bc(ctx, src1, src2, a->offs, cond);
+    return true;
+}
+
+TRANS(beq, gen_rr_bc, TCG_COND_EQ)
+TRANS(bne, gen_rr_bc, TCG_COND_NE)
+TRANS(blt, gen_rr_bc, TCG_COND_LT)
+TRANS(bge, gen_rr_bc, TCG_COND_GE)
+TRANS(bltu, gen_rr_bc, TCG_COND_LTU)
+TRANS(bgeu, gen_rr_bc, TCG_COND_GEU)
+TRANS(beqz, gen_rz_bc, TCG_COND_EQ)
+TRANS(bnez, gen_rz_bc, TCG_COND_NE)
+TRANS(bceqz, gen_cz_bc, TCG_COND_EQ)
+TRANS(bcnez, gen_cz_bc, TCG_COND_NE)