From: Ralf Baechle <ralf@linux-mips.org>
To: David Daney <ddaney.cavm@gmail.com>
Cc: "Hill, Steven" <sjhill@mips.com>,
"linux-mips@linux-mips.org" <linux-mips@linux-mips.org>,
"cernekee@gmail.com" <cernekee@gmail.com>,
"kevink@paralogos.com" <kevink@paralogos.com>
Subject: Re: [PATCH] [RFC] Proposed changes to eliminate 'union mips_instruction' type.
Date: Wed, 16 Jan 2013 15:16:18 +0100 [thread overview]
Message-ID: <20130116141618.GC26569@linux-mips.org> (raw)
In-Reply-To: <50F5DA93.2080706@gmail.com>
On Tue, Jan 15, 2013 at 02:39:15PM -0800, David Daney wrote:
So this should be fairly readable, far less code and in especially no
more variants for endianess except a single simple macro.
What do you think?
Ralf
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/include/asm/inst.h | 227 +++++++++++++++++--------------------------
1 file changed, 87 insertions(+), 140 deletions(-)
diff --git a/arch/mips/include/asm/inst.h b/arch/mips/include/asm/inst.h
index ab84064..442e7a4 100644
--- a/arch/mips/include/asm/inst.h
+++ b/arch/mips/include/asm/inst.h
@@ -196,154 +196,100 @@ enum lx_func {
* Damn ... bitfields depend from byteorder :-(
*/
#ifdef __MIPSEB__
-struct j_format { /* Jump format */
- unsigned int opcode : 6;
- unsigned int target : 26;
-};
-
-struct i_format { /* Immediate format (addi, lw, ...) */
- unsigned int opcode : 6;
- unsigned int rs : 5;
- unsigned int rt : 5;
- signed int simmediate : 16;
-};
-
-struct u_format { /* Unsigned immediate format (ori, xori, ...) */
- unsigned int opcode : 6;
- unsigned int rs : 5;
- unsigned int rt : 5;
- unsigned int uimmediate : 16;
-};
-
-struct c_format { /* Cache (>= R6000) format */
- unsigned int opcode : 6;
- unsigned int rs : 5;
- unsigned int c_op : 3;
- unsigned int cache : 2;
- unsigned int simmediate : 16;
-};
-
-struct r_format { /* Register format */
- unsigned int opcode : 6;
- unsigned int rs : 5;
- unsigned int rt : 5;
- unsigned int rd : 5;
- unsigned int re : 5;
- unsigned int func : 6;
-};
-
-struct p_format { /* Performance counter format (R10000) */
- unsigned int opcode : 6;
- unsigned int rs : 5;
- unsigned int rt : 5;
- unsigned int rd : 5;
- unsigned int re : 5;
- unsigned int func : 6;
-};
-
-struct f_format { /* FPU register format */
- unsigned int opcode : 6;
- unsigned int : 1;
- unsigned int fmt : 4;
- unsigned int rt : 5;
- unsigned int rd : 5;
- unsigned int re : 5;
- unsigned int func : 6;
-};
-
-struct ma_format { /* FPU multiply and add format (MIPS IV) */
- unsigned int opcode : 6;
- unsigned int fr : 5;
- unsigned int ft : 5;
- unsigned int fs : 5;
- unsigned int fd : 5;
- unsigned int func : 4;
- unsigned int fmt : 2;
-};
-
-struct b_format { /* BREAK and SYSCALL */
- unsigned int opcode:6;
- unsigned int code:20;
- unsigned int func:6;
-};
+#define BITFIELD_FIELD(field, more) \
+ field; \
+ more
#elif defined(__MIPSEL__)
-struct j_format { /* Jump format */
- unsigned int target : 26;
- unsigned int opcode : 6;
-};
-
-struct i_format { /* Immediate format */
- signed int simmediate : 16;
- unsigned int rt : 5;
- unsigned int rs : 5;
- unsigned int opcode : 6;
-};
-
-struct u_format { /* Unsigned immediate format */
- unsigned int uimmediate : 16;
- unsigned int rt : 5;
- unsigned int rs : 5;
- unsigned int opcode : 6;
-};
-
-struct c_format { /* Cache (>= R6000) format */
- unsigned int simmediate : 16;
- unsigned int cache : 2;
- unsigned int c_op : 3;
- unsigned int rs : 5;
- unsigned int opcode : 6;
-};
-
-struct r_format { /* Register format */
- unsigned int func : 6;
- unsigned int re : 5;
- unsigned int rd : 5;
- unsigned int rt : 5;
- unsigned int rs : 5;
- unsigned int opcode : 6;
-};
-
-struct p_format { /* Performance counter format (R10000) */
- unsigned int func : 6;
- unsigned int re : 5;
- unsigned int rd : 5;
- unsigned int rt : 5;
- unsigned int rs : 5;
- unsigned int opcode : 6;
-};
-
-struct f_format { /* FPU register format */
- unsigned int func : 6;
- unsigned int re : 5;
- unsigned int rd : 5;
- unsigned int rt : 5;
- unsigned int fmt : 4;
- unsigned int : 1;
- unsigned int opcode : 6;
-};
-
-struct ma_format { /* FPU multiply and add format (MIPS IV) */
- unsigned int fmt : 2;
- unsigned int func : 4;
- unsigned int fd : 5;
- unsigned int fs : 5;
- unsigned int ft : 5;
- unsigned int fr : 5;
- unsigned int opcode : 6;
-};
-
-struct b_format { /* BREAK and SYSCALL */
- unsigned int func:6;
- unsigned int code:20;
- unsigned int opcode:6;
-};
+#define BITFIELD_FIELD(field, more) \
+ more \
+ field;
#else /* !defined (__MIPSEB__) && !defined (__MIPSEL__) */
#error "MIPS but neither __MIPSEL__ nor __MIPSEB__?"
#endif
+struct j_format {
+ BITFIELD_FIELD(unsigned int opcode : 6, /* Jump format */
+ BITFIELD_FIELD(unsigned int target : 26,
+ ))
+};
+
+struct i_format { /* signed immediate format */
+ BITFIELD_FIELD(unsigned int opcode : 6,
+ BITFIELD_FIELD(unsigned int rs : 5,
+ BITFIELD_FIELD(unsigned int rt : 5,
+ BITFIELD_FIELD(signed int simmediate : 16,
+ ))))
+};
+
+struct u_format { /* unsigned immediate format */
+ BITFIELD_FIELD(unsigned int opcode : 6,
+ BITFIELD_FIELD(unsigned int rs : 5,
+ BITFIELD_FIELD(unsigned int rt : 5,
+ BITFIELD_FIELD(unsigned int uimmediate : 16,
+ ))))
+};
+
+struct c_format { /* Cache (>= R6000) format */
+ BITFIELD_FIELD(unsigned int opcode : 6,
+ BITFIELD_FIELD(unsigned int rs : 5,
+ BITFIELD_FIELD(unsigned int c_op : 3,
+ BITFIELD_FIELD(unsigned int cache : 2,
+ BITFIELD_FIELD(unsigned int simmediate : 16,
+ )))))
+};
+
+struct r_format { /* Register format */
+ BITFIELD_FIELD(unsigned int opcode : 6,
+ BITFIELD_FIELD(unsigned int rs : 5,
+ BITFIELD_FIELD(unsigned int rt : 5,
+ BITFIELD_FIELD(unsigned int rd : 5,
+ BITFIELD_FIELD(unsigned int re : 5,
+ BITFIELD_FIELD(unsigned int func : 6,
+ ))))))
+};
+
+struct p_format { /* Performance counter format (R10000) */
+ BITFIELD_FIELD(unsigned int opcode : 6,
+ BITFIELD_FIELD(unsigned int rs : 5,
+ BITFIELD_FIELD(unsigned int rt : 5,
+ BITFIELD_FIELD(unsigned int rd : 5,
+ BITFIELD_FIELD(unsigned int re : 5,
+ BITFIELD_FIELD(unsigned int func : 6,
+ ))))))
+};
+
+struct f_format { /* FPU register format */
+ BITFIELD_FIELD(unsigned int opcode : 6,
+ BITFIELD_FIELD(unsigned int : 1,
+ BITFIELD_FIELD(unsigned int fmt : 4,
+ BITFIELD_FIELD(unsigned int rt : 5,
+ BITFIELD_FIELD(unsigned int rd : 5,
+ BITFIELD_FIELD(unsigned int re : 5,
+ BITFIELD_FIELD(unsigned int func : 6,
+ )))))))
+};
+
+struct ma_format { /* FPU multiply and add format (MIPS IV) */
+ BITFIELD_FIELD(unsigned int opcode : 6,
+ BITFIELD_FIELD(unsigned int fr : 5,
+ BITFIELD_FIELD(unsigned int ft : 5,
+ BITFIELD_FIELD(unsigned int fs : 5,
+ BITFIELD_FIELD(unsigned int fd : 5,
+ BITFIELD_FIELD(unsigned int func : 4,
+ BITFIELD_FIELD(unsigned int fmt : 2,
+ )))))))
+};
+
+struct b_format { /* BREAK and SYSCALL */
+ BITFIELD_FIELD(unsigned int opcode : 6,
+ BITFIELD_FIELD(unsigned int code : 20,
+ BITFIELD_FIELD(unsigned int func : 6,
+ )))
+};
+
union mips_instruction {
unsigned int word;
unsigned short halfword[2];
@@ -353,6 +299,7 @@ union mips_instruction {
struct u_format u_format;
struct c_format c_format;
struct r_format r_format;
+ struct p_format p_format;
struct f_format f_format;
struct ma_format ma_format;
struct b_format b_format;
next prev parent reply other threads:[~2013-01-16 14:16 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-15 6:13 [PATCH] [RFC] Proposed changes to eliminate 'union mips_instruction' type Steven J. Hill
2013-01-15 8:24 ` Ralf Baechle
2013-01-15 19:41 ` David Daney
2013-01-15 22:19 ` Hill, Steven
2013-01-15 22:39 ` David Daney
2013-01-16 14:16 ` Ralf Baechle [this message]
2013-01-16 22:24 ` David Daney
2013-01-17 14:05 ` Ralf Baechle
2013-01-16 18:57 ` David Daney
2013-01-16 21:50 ` Hill, Steven
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