diff mbox series

[v3,10/16] target/mips: Introduce decode tree bindings for nanoMIPS ISA

Message ID 20241126140003.74871-11-philmd@linaro.org
State New
Headers show
Series target/mips: Convert nanoMIPS LSA opcode to decodetree | expand

Commit Message

Philippe Mathieu-Daudé Nov. 26, 2024, 1:59 p.m. UTC 
Introduce the nanoMIPS decodetree configs for the 16-bit,
32-bit and 48-bit instructions.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 target/mips/tcg/translate.h              |  3 +++
 target/mips/tcg/nanomips16.decode        |  8 ++++++++
 target/mips/tcg/nanomips32.decode        |  8 ++++++++
 target/mips/tcg/nanomips48.decode        |  8 ++++++++
 target/mips/tcg/nanomips_translate.c     | 15 +++++++++++++++
 target/mips/tcg/nanomips_translate.c.inc | 16 ++++++++++++++++
 target/mips/tcg/meson.build              |  4 ++++
 7 files changed, 62 insertions(+)
 create mode 100644 target/mips/tcg/nanomips16.decode
 create mode 100644 target/mips/tcg/nanomips32.decode
 create mode 100644 target/mips/tcg/nanomips48.decode
 create mode 100644 target/mips/tcg/nanomips_translate.c

Comments

Richard Henderson Nov. 26, 2024, 4:33 p.m. UTC | #1 
On 11/26/24 07:59, Philippe Mathieu-Daudé wrote:
> @@ -4480,6 +4480,22 @@ static int decode_isa_nanomips(CPUMIPSState *env, DisasContext *ctx)
>   
>       opcode = translator_lduw(env, &ctx->base, ctx->base.pc_next);
>       ctx->opcode = opcode;
> +    if (decode_isa_nanomips16(ctx, opcode)) {
> +        return 2;
> +    }
> +
> +    opcode <<= 16;
> +    opcode |= translator_lduw(env, &ctx->base, ctx->base.pc_next + 2);
> +    if (decode_isa_nanomips32(ctx, opcode)) {
> +        return 4;
> +    }
> +
> +    opcode <<= 16;
> +    opcode |= translator_lduw(env, &ctx->base, ctx->base.pc_next + 4);
> +    if (decode_isa_nanomips48(ctx, opcode)) {
> +        return 6;
> +    }

Oof.  Trivial to determine 32 vs 48 bit (NM_P48I), but much harder for 16 vs 32 bit.

Maybe this *would* be easier with decodetree --varinsnwidth.


r~
diff mbox series

Patch

diff --git a/target/mips/tcg/translate.h b/target/mips/tcg/translate.h
index 2a079cb28d9..7fe34a1d891 100644
--- a/target/mips/tcg/translate.h
+++ b/target/mips/tcg/translate.h
@@ -224,6 +224,9 @@  bool decode_64bit_enabled(DisasContext *ctx);
 /* decodetree generated */
 bool decode_isa_micromips16(DisasContext *ctx, uint16_t insn);
 bool decode_isa_micromips32(DisasContext *ctx, uint32_t insn);
+bool decode_isa_nanomips16(DisasContext *ctx, uint16_t insn);
+bool decode_isa_nanomips32(DisasContext *ctx, uint32_t insn);
+bool decode_isa_nanomips48(DisasContext *ctx, uint64_t insn);
 bool decode_isa_rel6(DisasContext *ctx, uint32_t insn);
 bool decode_ase_mips16e_16(DisasContext *ctx, uint16_t insn);
 bool decode_ase_mips16e_32(DisasContext *ctx, uint32_t insn);
diff --git a/target/mips/tcg/nanomips16.decode b/target/mips/tcg/nanomips16.decode
new file mode 100644
index 00000000000..81fdc68e98b
--- /dev/null
+++ b/target/mips/tcg/nanomips16.decode
@@ -0,0 +1,8 @@ 
+# nanoMIPS32 16-bit instruction set extensions
+#
+# Copyright (C) 2021  Philippe Mathieu-Daudé
+#
+# SPDX-License-Identifier: LGPL-2.1-or-later
+#
+# Reference: nanoMIPS32 Instruction Set Technical Reference Manual
+#            (Document Number: MD01247)
diff --git a/target/mips/tcg/nanomips32.decode b/target/mips/tcg/nanomips32.decode
new file mode 100644
index 00000000000..9cecf1e13d3
--- /dev/null
+++ b/target/mips/tcg/nanomips32.decode
@@ -0,0 +1,8 @@ 
+# nanoMIPS32 32-bit instruction set extensions
+#
+# Copyright (C) 2021  Philippe Mathieu-Daudé
+#
+# SPDX-License-Identifier: LGPL-2.1-or-later
+#
+# Reference: nanoMIPS32 Instruction Set Technical Reference Manual
+#            (Document Number: MD01247)
diff --git a/target/mips/tcg/nanomips48.decode b/target/mips/tcg/nanomips48.decode
new file mode 100644
index 00000000000..696cc15607a
--- /dev/null
+++ b/target/mips/tcg/nanomips48.decode
@@ -0,0 +1,8 @@ 
+# nanoMIPS32 48-bit instruction set extensions
+#
+# Copyright (C) 2021  Philippe Mathieu-Daudé
+#
+# SPDX-License-Identifier: LGPL-2.1-or-later
+#
+# Reference: nanoMIPS32 Instruction Set Technical Reference Manual
+#            (Document Number: MD01247)
diff --git a/target/mips/tcg/nanomips_translate.c b/target/mips/tcg/nanomips_translate.c
new file mode 100644
index 00000000000..335a32845ed
--- /dev/null
+++ b/target/mips/tcg/nanomips_translate.c
@@ -0,0 +1,15 @@ 
+/*
+ * MIPS emulation for QEMU - nanoMIPS translation routines
+ *
+ * Copyright (c) 2021 Philippe Mathieu-Daudé <f4bug@amsat.org>
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "translate.h"
+
+/* Include the auto-generated decoders.  */
+#include "decode-nanomips16.c.inc"
+#include "decode-nanomips32.c.inc"
+#include "decode-nanomips48.c.inc"
diff --git a/target/mips/tcg/nanomips_translate.c.inc b/target/mips/tcg/nanomips_translate.c.inc
index e0a920bdb3a..5d021f01128 100644
--- a/target/mips/tcg/nanomips_translate.c.inc
+++ b/target/mips/tcg/nanomips_translate.c.inc
@@ -4480,6 +4480,22 @@  static int decode_isa_nanomips(CPUMIPSState *env, DisasContext *ctx)
 
     opcode = translator_lduw(env, &ctx->base, ctx->base.pc_next);
     ctx->opcode = opcode;
+    if (decode_isa_nanomips16(ctx, opcode)) {
+        return 2;
+    }
+
+    opcode <<= 16;
+    opcode |= translator_lduw(env, &ctx->base, ctx->base.pc_next + 2);
+    if (decode_isa_nanomips32(ctx, opcode)) {
+        return 4;
+    }
+
+    opcode <<= 16;
+    opcode |= translator_lduw(env, &ctx->base, ctx->base.pc_next + 4);
+    if (decode_isa_nanomips48(ctx, opcode)) {
+        return 6;
+    }
+
     rt = decode_gpr_gpr3(NANOMIPS_EXTRACT_RT3(ctx->opcode));
     rs = decode_gpr_gpr3(NANOMIPS_EXTRACT_RS3(ctx->opcode));
     rd = decode_gpr_gpr3(NANOMIPS_EXTRACT_RD3(ctx->opcode));
diff --git a/target/mips/tcg/meson.build b/target/mips/tcg/meson.build
index ca70769912c..f674819e6a8 100644
--- a/target/mips/tcg/meson.build
+++ b/target/mips/tcg/meson.build
@@ -4,6 +4,9 @@  gen = [
   decodetree.process('micromips16.decode', extra_args: ['--decode=decode_isa_micromips16', '--insnwidth=16']),
   decodetree.process('micromips32.decode', extra_args: ['--decode=decode_isa_micromips32']),
   decodetree.process('rel6.decode', extra_args: ['--decode=decode_isa_rel6']),
+  decodetree.process('nanomips16.decode', extra_args: ['--decode=decode_isa_nanomips16', '--insnwidth=16']),
+  decodetree.process('nanomips32.decode', extra_args: ['--decode=decode_isa_nanomips32']),
+  decodetree.process('nanomips48.decode', extra_args: ['--decode=decode_isa_nanomips48', '--insnwidth=48']),
   decodetree.process('msa.decode', extra_args: '--decode=decode_ase_msa'),
   decodetree.process('tx79.decode', extra_args: '--static-decode=decode_tx79'),
   decodetree.process('vr54xx.decode', extra_args: '--decode=decode_ext_vr54xx'),
@@ -24,6 +27,7 @@  mips_ss.add(files(
   'mips16e_translate.c',
   'msa_helper.c',
   'msa_translate.c',
+  'nanomips_translate.c',
   'op_helper.c',
   'rel6_translate.c',
   'translate.c',