[Qemu-devel] [PULL 20/34] target/riscv: Remove manual decoding from gen_branch()

[Palmer Dabbelt <palmer@sifive.com>]

From: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>

We now utilizes argument-sets of decodetree such that no manual
decoding is necessary.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Peer Adelt <peer.adelt@hni.uni-paderborn.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
---
 target/riscv/insn_trans/trans_rvi.inc.c | 46 +++++++++++++++++-------
 target/riscv/translate.c                | 47 -------------------------
 2 files changed, 33 insertions(+), 60 deletions(-)

diff --git a/target/riscv/insn_trans/trans_rvi.inc.c b/target/riscv/insn_trans/trans_rvi.inc.c
index 631a88906bce..ae4b0a2bcb78 100644
--- a/target/riscv/insn_trans/trans_rvi.inc.c
+++ b/target/riscv/insn_trans/trans_rvi.inc.c
@@ -72,41 +72,61 @@ static bool trans_jalr(DisasContext *ctx, arg_jalr *a)
     return true;
 }
 
-static bool trans_beq(DisasContext *ctx, arg_beq *a)
+static bool gen_branch(DisasContext *ctx, arg_b *a, TCGCond cond)
 {
-    gen_branch(ctx, OPC_RISC_BEQ, a->rs1, a->rs2, a->imm);
+    TCGLabel *l = gen_new_label();
+    TCGv source1, source2;
+    source1 = tcg_temp_new();
+    source2 = tcg_temp_new();
+    gen_get_gpr(source1, a->rs1);
+    gen_get_gpr(source2, a->rs2);
+
+    tcg_gen_brcond_tl(cond, source1, source2, l);
+    gen_goto_tb(ctx, 1, ctx->pc_succ_insn);
+    gen_set_label(l); /* branch taken */
+
+    if (!has_ext(ctx, RVC) && ((ctx->base.pc_next + a->imm) & 0x3)) {
+        /* misaligned */
+        gen_exception_inst_addr_mis(ctx);
+    } else {
+        gen_goto_tb(ctx, 0, ctx->base.pc_next + a->imm);
+    }
+    ctx->base.is_jmp = DISAS_NORETURN;
+
+    tcg_temp_free(source1);
+    tcg_temp_free(source2);
+
     return true;
 }
 
+static bool trans_beq(DisasContext *ctx, arg_beq *a)
+{
+    return gen_branch(ctx, a, TCG_COND_EQ);
+}
+
 static bool trans_bne(DisasContext *ctx, arg_bne *a)
 {
-    gen_branch(ctx, OPC_RISC_BNE, a->rs1, a->rs2, a->imm);
-    return true;
+    return gen_branch(ctx, a, TCG_COND_NE);
 }
 
 static bool trans_blt(DisasContext *ctx, arg_blt *a)
 {
-    gen_branch(ctx, OPC_RISC_BLT, a->rs1, a->rs2, a->imm);
-    return true;
+    return gen_branch(ctx, a, TCG_COND_LT);
 }
 
 static bool trans_bge(DisasContext *ctx, arg_bge *a)
 {
-    gen_branch(ctx, OPC_RISC_BGE, a->rs1, a->rs2, a->imm);
-    return true;
+    return gen_branch(ctx, a, TCG_COND_GE);
 }
 
 static bool trans_bltu(DisasContext *ctx, arg_bltu *a)
 {
-    gen_branch(ctx, OPC_RISC_BLTU, a->rs1, a->rs2, a->imm);
-    return true;
+    return gen_branch(ctx, a, TCG_COND_LTU);
 }
 
 static bool trans_bgeu(DisasContext *ctx, arg_bgeu *a)
 {
-
-    gen_branch(ctx, OPC_RISC_BGEU, a->rs1, a->rs2, a->imm);
-    return true;
+    return gen_branch(ctx, a, TCG_COND_GEU);
 }
 
 static bool trans_lb(DisasContext *ctx, arg_lb *a)
diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index 9dee2ec24287..a3d5cdbad82d 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -531,53 +531,6 @@ static void gen_jal(DisasContext *ctx, int rd, target_ulong imm)
     ctx->base.is_jmp = DISAS_NORETURN;
 }
 
-static void gen_branch(DisasContext *ctx, uint32_t opc, int rs1, int rs2,
-                       target_long bimm)
-{
-    TCGLabel *l = gen_new_label();
-    TCGv source1, source2;
-    source1 = tcg_temp_new();
-    source2 = tcg_temp_new();
-    gen_get_gpr(source1, rs1);
-    gen_get_gpr(source2, rs2);
-
-    switch (opc) {
-    case OPC_RISC_BEQ:
-        tcg_gen_brcond_tl(TCG_COND_EQ, source1, source2, l);
-        break;
-    case OPC_RISC_BNE:
-        tcg_gen_brcond_tl(TCG_COND_NE, source1, source2, l);
-        break;
-    case OPC_RISC_BLT:
-        tcg_gen_brcond_tl(TCG_COND_LT, source1, source2, l);
-        break;
-    case OPC_RISC_BGE:
-        tcg_gen_brcond_tl(TCG_COND_GE, source1, source2, l);
-        break;
-    case OPC_RISC_BLTU:
-        tcg_gen_brcond_tl(TCG_COND_LTU, source1, source2, l);
-        break;
-    case OPC_RISC_BGEU:
-        tcg_gen_brcond_tl(TCG_COND_GEU, source1, source2, l);
-        break;
-    default:
-        gen_exception_illegal(ctx);
-        return;
-    }
-    tcg_temp_free(source1);
-    tcg_temp_free(source2);
-
-    gen_goto_tb(ctx, 1, ctx->pc_succ_insn);
-    gen_set_label(l); /* branch taken */
-    if (!has_ext(ctx, RVC) && ((ctx->base.pc_next + bimm) & 0x3)) {
-        /* misaligned */
-        gen_exception_inst_addr_mis(ctx);
-    } else {
-        gen_goto_tb(ctx, 0, ctx->base.pc_next + bimm);
-    }
-    ctx->base.is_jmp = DISAS_NORETURN;
-}
-
 static void gen_load(DisasContext *ctx, uint32_t opc, int rd, int rs1,
         target_long imm)
 {
-- 
2.18.1