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From: Vincent Chen <vincentc@andestech.com>
To: linux-kernel@vger.kernel.org, arnd@arndb.de,
	linux-arch@vger.kernel.org, greentime@andestech.com,
	green.hu@gmail.com, deanbo422@gmail.com
Cc: vincentc@andestech.com
Subject: [PATCH v2 3/3] math-emu: Use statement expressions to fix Wshift-count-overflow warning
Date: Mon, 27 May 2019 14:17:21 +0800	[thread overview]
Message-ID: <1558937841-4222-4-git-send-email-vincentc@andestech.com> (raw)
In-Reply-To: <1558937841-4222-1-git-send-email-vincentc@andestech.com>

To avoid "shift count >= width of type" warning, using statement
expressions to implement the conditional controlling before constant shift

The modification in op-2.h is taken from the glibc
commit 'sysdeps/unix/sysv/lin ("fe0b1e854ad32")'.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
---
 Changes in v2
 - This is an new patch to fix Wshift-count-overflow warning

 include/math-emu/op-2.h      |   17 +++++++----------
 include/math-emu/op-common.h |   11 ++++++-----
 2 files changed, 13 insertions(+), 15 deletions(-)

diff --git a/include/math-emu/op-2.h b/include/math-emu/op-2.h
index 13a374f..244522b 100644
--- a/include/math-emu/op-2.h
+++ b/include/math-emu/op-2.h
@@ -567,16 +567,13 @@
  */
 
 #define _FP_FRAC_ASSEMBLE_2(r, X, rsize)	\
-  do {						\
-    if (rsize <= _FP_W_TYPE_SIZE)		\
-      r = X##_f0;				\
-    else					\
-      {						\
-	r = X##_f1;				\
-	r <<= _FP_W_TYPE_SIZE;			\
-	r += X##_f0;				\
-      }						\
-  } while (0)
+	(void) (((rsize) <= _FP_W_TYPE_SIZE)	\
+		? ({ (r) = X##_f0; })		\
+		: ({				\
+		     (r) = X##_f1;		\
+		     (r) <<= _FP_W_TYPE_SIZE;	\
+		     (r) += X##_f0;		\
+		    }))
 
 #define _FP_FRAC_DISASSEMBLE_2(X, r, rsize)				\
   do {									\
diff --git a/include/math-emu/op-common.h b/include/math-emu/op-common.h
index 6bdf8c6..f37d128 100644
--- a/include/math-emu/op-common.h
+++ b/include/math-emu/op-common.h
@@ -795,11 +795,12 @@
 	  ur_ = (unsigned rtype) -r;					\
 	else								\
 	  ur_ = (unsigned rtype) r;					\
-	if (rsize <= _FP_W_TYPE_SIZE)					\
-	  __FP_CLZ(X##_e, ur_);						\
-	else								\
-	  __FP_CLZ_2(X##_e, (_FP_W_TYPE)(ur_ >> _FP_W_TYPE_SIZE), 	\
-		     (_FP_W_TYPE)ur_);					\
+	(void) (((rsize) <= _FP_W_TYPE_SIZE)				\
+		? ({ __FP_CLZ(X##_e, ur_); })				\
+		: ({							\
+		     __FP_CLZ_2(X##_e, (_FP_W_TYPE)(ur_ >> _FP_W_TYPE_SIZE),  \
+							    (_FP_W_TYPE)ur_); \
+		  }));							\
 	if (rsize < _FP_W_TYPE_SIZE)					\
 		X##_e -= (_FP_W_TYPE_SIZE - rsize);			\
 	X##_e = rsize - X##_e - 1;					\
-- 
1.7.1

  parent reply	other threads:[~2019-05-27  6:17 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-27  6:17 [PATCH v2 0/3] nds32: Prevent FPU emulator from incorrectly modifying IEX status Vincent Chen
2019-05-27  6:17 ` Vincent Chen
2019-05-27  6:17 ` [PATCH v2 1/3] nds32: Avoid IEX status being incorrectly modified Vincent Chen
2019-05-27  6:17   ` Vincent Chen
2019-05-27  6:17 ` [PATCH v2 2/3] nds32: add new emulations for floating point instruction Vincent Chen
2019-05-27  6:17   ` Vincent Chen
2019-05-27  6:17 ` Vincent Chen [this message]
2019-05-27  6:17   ` [PATCH v2 3/3] math-emu: Use statement expressions to fix Wshift-count-overflow warning Vincent Chen

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