linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v2 0/3] nds32: Prevent FPU emulator from incorrectly modifying IEX status
@ 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
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Vincent Chen @ 2019-05-27  6:17 UTC (permalink / raw)
  To: linux-kernel, arnd, linux-arch, greentime, green.hu, deanbo422; +Cc: vincentc

  In order for kernel to capture each denormalized output, the UDF
trapping enable bit is always raised in $fpcsr. Because underflow case will
issue not an underflow exception but also an inexact exception, it causes
that the IEX, IEX cumulative exception, flag in $fpcsr to be raised in each
denormalized output handling. To make the emulation transparent to the
user, the emulator needs to clear the IEX flag in $fpcsr if the result is a
denormalized number. However, if the IEX flag has been raised before this
floating point emulation, this cleanup may be incorrect. To avoid the IEX
flags in $fpcsr be raised in each denormalized output handling, the 1st
patch always enable IEX trap to fix this issue.

  The existing floating point emulations is only available for floating
instruction that possibly issue denormalized input and underflow
exceptions. These existing FPU emulations are not sufficient when IEx
Trap is enabled because some floating point instructions only issue inexact
exception. The 2nd patch adds the emulations of such floating point
instructions.

  While compiling the files of 2nd patch, compiler thinks the length of
bit-shift may be greater than the bit length of data type so that many
Wshift-count-overflow warning is issued. These warnings are fixed in the
3rd patch.

Vincent Chen (3):
  nds32: Avoid IEX status being incorrectly modified
  nds32: add new emulations for floating point instruction
  math-emu: Use statement expressions to fix Wshift-count-overflow
    warning

 arch/nds32/include/asm/bitfield.h            |    2 +-
 arch/nds32/include/asm/fpu.h                 |    2 +-
 arch/nds32/include/asm/fpuemu.h              |   12 +++++
 arch/nds32/include/asm/syscalls.h            |    2 +-
 arch/nds32/include/uapi/asm/fp_udfiex_crtl.h |   16 +++++++
 arch/nds32/include/uapi/asm/sigcontext.h     |   24 ++++++++---
 arch/nds32/include/uapi/asm/udftrap.h        |   13 ------
 arch/nds32/include/uapi/asm/unistd.h         |    4 +-
 arch/nds32/kernel/fpu.c                      |   15 +++----
 arch/nds32/kernel/sys_nds32.c                |   26 ++++++-----
 arch/nds32/math-emu/Makefile                 |    5 ++-
 arch/nds32/math-emu/fd2si.c                  |   30 +++++++++++++
 arch/nds32/math-emu/fd2siz.c                 |   30 +++++++++++++
 arch/nds32/math-emu/fd2ui.c                  |   30 +++++++++++++
 arch/nds32/math-emu/fd2uiz.c                 |   30 +++++++++++++
 arch/nds32/math-emu/fpuemu.c                 |   57 ++++++++++++++++++++++++--
 arch/nds32/math-emu/fs2si.c                  |   29 +++++++++++++
 arch/nds32/math-emu/fs2siz.c                 |   29 +++++++++++++
 arch/nds32/math-emu/fs2ui.c                  |   29 +++++++++++++
 arch/nds32/math-emu/fs2uiz.c                 |   30 +++++++++++++
 arch/nds32/math-emu/fsi2d.c                  |   22 ++++++++++
 arch/nds32/math-emu/fsi2s.c                  |   22 ++++++++++
 arch/nds32/math-emu/fui2d.c                  |   22 ++++++++++
 arch/nds32/math-emu/fui2s.c                  |   22 ++++++++++
 include/math-emu/op-2.h                      |   17 +++-----
 include/math-emu/op-common.h                 |   11 +++--
 26 files changed, 465 insertions(+), 66 deletions(-)
 create mode 100644 arch/nds32/include/uapi/asm/fp_udfiex_crtl.h
 delete mode 100644 arch/nds32/include/uapi/asm/udftrap.h
 create mode 100644 arch/nds32/math-emu/fd2si.c
 create mode 100644 arch/nds32/math-emu/fd2siz.c
 create mode 100644 arch/nds32/math-emu/fd2ui.c
 create mode 100644 arch/nds32/math-emu/fd2uiz.c
 create mode 100644 arch/nds32/math-emu/fs2si.c
 create mode 100644 arch/nds32/math-emu/fs2siz.c
 create mode 100644 arch/nds32/math-emu/fs2ui.c
 create mode 100644 arch/nds32/math-emu/fs2uiz.c
 create mode 100644 arch/nds32/math-emu/fsi2d.c
 create mode 100644 arch/nds32/math-emu/fsi2s.c
 create mode 100644 arch/nds32/math-emu/fui2d.c
 create mode 100644 arch/nds32/math-emu/fui2s.c


^ permalink raw reply	[flat|nested] 4+ messages in thread
* [PATCH v2 1/3] nds32: Avoid IEX status being incorrectly modified
  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 2/3] nds32: add new emulations for floating point instruction Vincent Chen
  2019-05-27  6:17 ` [PATCH v2 3/3] math-emu: Use statement expressions to fix Wshift-count-overflow warning Vincent Chen
  2 siblings, 0 replies; 4+ messages in thread
From: Vincent Chen @ 2019-05-27  6:17 UTC (permalink / raw)
  To: linux-kernel, arnd, linux-arch, greentime, green.hu, deanbo422; +Cc: vincentc

  In order for kernel to capture each denormalized output, the UDF
trapping enable bit is always raised in $fpcsr. Because underflow case will
issue not an underflow exception but also an inexact exception, it causes
that the IEX, IEX cumulative exception, flag in $fpcsr to be raised in each
denormalized output handling. To make the emulation transparent to the
user, the emulator needs to clear the IEX flag in $fpcsr if the result is a
denormalized number. However, if the IEX flag has been raised before this
floating point emulation, this cleanup may be incorrect. To avoid the IEX
flags in $fpcsr be raised in each denormalized output handling, the IEX
trap shall be always enabled.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
---
 Changes in v2
 - No changes


 arch/nds32/include/asm/bitfield.h            |    2 +-
 arch/nds32/include/asm/fpu.h                 |    2 +-
 arch/nds32/include/asm/syscalls.h            |    2 +-
 arch/nds32/include/uapi/asm/fp_udfiex_crtl.h |   16 ++++++++++++++++
 arch/nds32/include/uapi/asm/sigcontext.h     |   24 +++++++++++++++++-------
 arch/nds32/include/uapi/asm/udftrap.h        |   13 -------------
 arch/nds32/include/uapi/asm/unistd.h         |    4 ++--
 arch/nds32/kernel/fpu.c                      |   15 ++++++---------
 arch/nds32/kernel/sys_nds32.c                |   26 ++++++++++++++------------
 9 files changed, 58 insertions(+), 46 deletions(-)
 create mode 100644 arch/nds32/include/uapi/asm/fp_udfiex_crtl.h
 delete mode 100644 arch/nds32/include/uapi/asm/udftrap.h

diff --git a/arch/nds32/include/asm/bitfield.h b/arch/nds32/include/asm/bitfield.h
index 7414fcb..03bbb6d 100644
--- a/arch/nds32/include/asm/bitfield.h
+++ b/arch/nds32/include/asm/bitfield.h
@@ -937,7 +937,7 @@
 #define FPCSR_mskDNIT           ( 0x1  << FPCSR_offDNIT )
 #define FPCSR_mskRIT		( 0x1  << FPCSR_offRIT )
 #define FPCSR_mskALL		(FPCSR_mskIVO | FPCSR_mskDBZ | FPCSR_mskOVF | FPCSR_mskUDF | FPCSR_mskIEX)
-#define FPCSR_mskALLE_NO_UDFE	(FPCSR_mskIVOE | FPCSR_mskDBZE | FPCSR_mskOVFE | FPCSR_mskIEXE)
+#define FPCSR_mskALLE_NO_UDF_IEXE (FPCSR_mskIVOE | FPCSR_mskDBZE | FPCSR_mskOVFE)
 #define FPCSR_mskALLE		(FPCSR_mskIVOE | FPCSR_mskDBZE | FPCSR_mskOVFE | FPCSR_mskUDFE | FPCSR_mskIEXE)
 #define FPCSR_mskALLT           (FPCSR_mskIVOT | FPCSR_mskDBZT | FPCSR_mskOVFT | FPCSR_mskUDFT | FPCSR_mskIEXT |FPCSR_mskDNIT | FPCSR_mskRIT)
 
diff --git a/arch/nds32/include/asm/fpu.h b/arch/nds32/include/asm/fpu.h
index 019f1bc..8294ed4 100644
--- a/arch/nds32/include/asm/fpu.h
+++ b/arch/nds32/include/asm/fpu.h
@@ -36,7 +36,7 @@
  * enabled by default and kerenl will re-execute it by fpu emulator
  * when getting underflow exception.
  */
-#define FPCSR_INIT  FPCSR_mskUDFE
+#define FPCSR_INIT  (FPCSR_mskUDFE | FPCSR_mskIEXE)
 #else
 #define FPCSR_INIT  0x0UL
 #endif
diff --git a/arch/nds32/include/asm/syscalls.h b/arch/nds32/include/asm/syscalls.h
index da32101..b9c9bec 100644
--- a/arch/nds32/include/asm/syscalls.h
+++ b/arch/nds32/include/asm/syscalls.h
@@ -7,7 +7,7 @@
 asmlinkage long sys_cacheflush(unsigned long addr, unsigned long len, unsigned int op);
 asmlinkage long sys_fadvise64_64_wrapper(int fd, int advice, loff_t offset, loff_t len);
 asmlinkage long sys_rt_sigreturn_wrapper(void);
-asmlinkage long sys_udftrap(int option);
+asmlinkage long sys_fp_udfiex_crtl(int cmd, int act);
 
 #include <asm-generic/syscalls.h>
 
diff --git a/arch/nds32/include/uapi/asm/fp_udfiex_crtl.h b/arch/nds32/include/uapi/asm/fp_udfiex_crtl.h
new file mode 100644
index 0000000..d54a5d6
--- /dev/null
+++ b/arch/nds32/include/uapi/asm/fp_udfiex_crtl.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2005-2019 Andes Technology Corporation */
+#ifndef	_FP_UDF_IEX_CRTL_H
+#define	_FP_UDF_IEX_CRTL_H
+
+/*
+ * The cmd list of sys_fp_udfiex_crtl()
+ */
+/* Disable UDF or IEX trap based on the content of parameter act */
+#define DISABLE_UDF_IEX_TRAP	0
+/* Enable UDF or IEX trap based on the content of parameter act */
+#define ENABLE_UDF_IEX_TRAP	1
+/* Get current status of UDF and IEX trap */
+#define GET_UDF_IEX_TRAP	2
+
+#endif /* _FP_UDF_IEX_CRTL_H */
diff --git a/arch/nds32/include/uapi/asm/sigcontext.h b/arch/nds32/include/uapi/asm/sigcontext.h
index 58afc41..b536340 100644
--- a/arch/nds32/include/uapi/asm/sigcontext.h
+++ b/arch/nds32/include/uapi/asm/sigcontext.h
@@ -13,14 +13,24 @@ struct fpu_struct {
 	unsigned long long fd_regs[32];
 	unsigned long fpcsr;
 	/*
-	 * UDF_trap is used to recognize whether underflow trap is enabled
-	 * or not. When UDF_trap == 1, this process will be traped and then
-	 * get a SIGFPE signal when encountering an underflow exception.
-	 * UDF_trap is only modified through setfputrap syscall. Therefore,
-	 * UDF_trap needn't be saved or loaded to context in each context
-	 * switch.
+	 * When CONFIG_SUPPORT_DENORMAL_ARITHMETIC is defined, kernel prevents
+	 * hardware from treating the denormalized output as an underflow case
+	 * and rounding it to a normal number. Hence kernel enables the UDF and
+	 * IEX trap in the fpcsr register to step in the calculation.
+	 * However, the UDF and IEX trap enable bit in $fpcsr also lose
+	 * their use.
+	 *
+	 * UDF_IEX_trap replaces the feature of UDF and IEX trap enable bit in
+	 * $fpcsr to control the trap of underflow and inexact. The bit filed
+	 * of UDF_IEX_trap is the same as $fpcsr, 10th bit is used to enable UDF
+	 * exception trapping and 11th bit is used to enable IEX exception
+	 * trapping.
+	 *
+	 * UDF_IEX_trap is only modified through fp_udfiex_crtl syscall.
+	 * Therefore, UDF_IEX_trap needn't be saved and restored in each
+	 * context switch.
 	 */
-	unsigned long UDF_trap;
+	unsigned long UDF_IEX_trap;
 };
 
 struct zol_struct {
diff --git a/arch/nds32/include/uapi/asm/udftrap.h b/arch/nds32/include/uapi/asm/udftrap.h
deleted file mode 100644
index 433f79d..0000000
--- a/arch/nds32/include/uapi/asm/udftrap.h
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/* Copyright (C) 2005-2018 Andes Technology Corporation */
-#ifndef	_ASM_SETFPUTRAP
-#define	_ASM_SETFPUTRAP
-
-/*
- * Options for setfputrap system call
- */
-#define	DISABLE_UDFTRAP	0	/* disable underflow exception trap */
-#define	ENABLE_UDFTRAP	1	/* enable undeflos exception trap */
-#define	GET_UDFTRAP	2	/* only get undeflos exception trap status */
-
-#endif /* _ASM_CACHECTL */
diff --git a/arch/nds32/include/uapi/asm/unistd.h b/arch/nds32/include/uapi/asm/unistd.h
index 4ec8f54..6b9ff90 100644
--- a/arch/nds32/include/uapi/asm/unistd.h
+++ b/arch/nds32/include/uapi/asm/unistd.h
@@ -11,6 +11,6 @@
 
 /* Additional NDS32 specific syscalls. */
 #define __NR_cacheflush		(__NR_arch_specific_syscall)
-#define __NR_udftrap		(__NR_arch_specific_syscall + 1)
+#define __NR_fp_udfiex_crtl	(__NR_arch_specific_syscall + 1)
 __SYSCALL(__NR_cacheflush, sys_cacheflush)
-__SYSCALL(__NR_udftrap, sys_udftrap)
+__SYSCALL(__NR_fp_udfiex_crtl, sys_fp_udfiex_crtl)
diff --git a/arch/nds32/kernel/fpu.c b/arch/nds32/kernel/fpu.c
index fddd40c..cf0b876 100644
--- a/arch/nds32/kernel/fpu.c
+++ b/arch/nds32/kernel/fpu.c
@@ -14,7 +14,7 @@
 	.fd_regs = {[0 ... 31] = sNAN64},
 	.fpcsr = FPCSR_INIT,
 #if IS_ENABLED(CONFIG_SUPPORT_DENORMAL_ARITHMETIC)
-	.UDF_trap = 0
+	.UDF_IEX_trap = 0
 #endif
 };
 
@@ -178,7 +178,7 @@ inline void do_fpu_context_switch(struct pt_regs *regs)
 		/* First time FPU user.  */
 		load_fpu(&init_fpuregs);
 #if IS_ENABLED(CONFIG_SUPPORT_DENORMAL_ARITHMETIC)
-		current->thread.fpu.UDF_trap = init_fpuregs.UDF_trap;
+		current->thread.fpu.UDF_IEX_trap = init_fpuregs.UDF_IEX_trap;
 #endif
 		set_used_math();
 	}
@@ -206,7 +206,7 @@ inline void handle_fpu_exception(struct pt_regs *regs)
 	unsigned int fpcsr;
 	int si_code = 0, si_signo = SIGFPE;
 #if IS_ENABLED(CONFIG_SUPPORT_DENORMAL_ARITHMETIC)
-	unsigned long redo_except = FPCSR_mskDNIT|FPCSR_mskUDFT;
+	unsigned long redo_except = FPCSR_mskDNIT|FPCSR_mskUDFT|FPCSR_mskIEXT;
 #else
 	unsigned long redo_except = FPCSR_mskDNIT;
 #endif
@@ -215,21 +215,18 @@ inline void handle_fpu_exception(struct pt_regs *regs)
 	fpcsr = current->thread.fpu.fpcsr;
 
 	if (fpcsr & redo_except) {
-#if IS_ENABLED(CONFIG_SUPPORT_DENORMAL_ARITHMETIC)
-		if (fpcsr & FPCSR_mskUDFT)
-			current->thread.fpu.fpcsr &= ~FPCSR_mskIEX;
-#endif
 		si_signo = do_fpuemu(regs, &current->thread.fpu);
 		fpcsr = current->thread.fpu.fpcsr;
-		if (!si_signo)
+		if (!si_signo) {
+			current->thread.fpu.fpcsr &= ~(redo_except);
 			goto done;
+		}
 	} else if (fpcsr & FPCSR_mskRIT) {
 		if (!user_mode(regs))
 			do_exit(SIGILL);
 		si_signo = SIGILL;
 	}
 
-
 	switch (si_signo) {
 	case SIGFPE:
 		fill_sigfpe_signo(fpcsr, &si_code);
diff --git a/arch/nds32/kernel/sys_nds32.c b/arch/nds32/kernel/sys_nds32.c
index 0835277..cb2d1e2 100644
--- a/arch/nds32/kernel/sys_nds32.c
+++ b/arch/nds32/kernel/sys_nds32.c
@@ -6,8 +6,8 @@
 
 #include <asm/cachectl.h>
 #include <asm/proc-fns.h>
-#include <asm/udftrap.h>
 #include <asm/fpu.h>
+#include <asm/fp_udfiex_crtl.h>
 
 SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
 	       unsigned long, prot, unsigned long, flags,
@@ -51,31 +51,33 @@
 	return 0;
 }
 
-SYSCALL_DEFINE1(udftrap, int, option)
+SYSCALL_DEFINE2(fp_udfiex_crtl, unsigned int, cmd, unsigned int, act)
 {
 #if IS_ENABLED(CONFIG_SUPPORT_DENORMAL_ARITHMETIC)
-	int old_udftrap;
+	int old_udf_iex;
 
 	if (!used_math()) {
 		load_fpu(&init_fpuregs);
-		current->thread.fpu.UDF_trap = init_fpuregs.UDF_trap;
+		current->thread.fpu.UDF_IEX_trap = init_fpuregs.UDF_IEX_trap;
 		set_used_math();
 	}
 
-	old_udftrap = current->thread.fpu.UDF_trap;
-	switch (option) {
-	case DISABLE_UDFTRAP:
-		current->thread.fpu.UDF_trap = 0;
+	old_udf_iex = current->thread.fpu.UDF_IEX_trap;
+	act &= (FPCSR_mskUDFE | FPCSR_mskIEXE);
+
+	switch (cmd) {
+	case DISABLE_UDF_IEX_TRAP:
+		current->thread.fpu.UDF_IEX_trap &= ~act;
 		break;
-	case ENABLE_UDFTRAP:
-		current->thread.fpu.UDF_trap = FPCSR_mskUDFE;
+	case ENABLE_UDF_IEX_TRAP:
+		current->thread.fpu.UDF_IEX_trap |= act;
 		break;
-	case GET_UDFTRAP:
+	case GET_UDF_IEX_TRAP:
 		break;
 	default:
 		return -EINVAL;
 	}
-	return old_udftrap;
+	return old_udf_iex;
 #else
 	return -ENOTSUPP;
 #endif
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread
* [PATCH v2 2/3] nds32: add new emulations for floating point instruction
  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 ` [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 3/3] math-emu: Use statement expressions to fix Wshift-count-overflow warning Vincent Chen
  2 siblings, 0 replies; 4+ messages in thread
From: Vincent Chen @ 2019-05-27  6:17 UTC (permalink / raw)
  To: linux-kernel, arnd, linux-arch, greentime, green.hu, deanbo422; +Cc: vincentc

The existing floating point emulations is only available for floating
instruction that possibly issue denormalized input and underflow
exceptions. These existing FPU emulations are not sufficient when IEx
Trap is enabled because some floating point instructions only issue inexact
exception. This patch adds the emulations of such floating point
instructions.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
---
 Changes in v2
 - No changes

 arch/nds32/include/asm/fpuemu.h |   12 ++++++++
 arch/nds32/math-emu/Makefile    |    5 +++-
 arch/nds32/math-emu/fd2si.c     |   30 ++++++++++++++++++++
 arch/nds32/math-emu/fd2siz.c    |   30 ++++++++++++++++++++
 arch/nds32/math-emu/fd2ui.c     |   30 ++++++++++++++++++++
 arch/nds32/math-emu/fd2uiz.c    |   30 ++++++++++++++++++++
 arch/nds32/math-emu/fpuemu.c    |   57 ++++++++++++++++++++++++++++++++++++---
 arch/nds32/math-emu/fs2si.c     |   29 ++++++++++++++++++++
 arch/nds32/math-emu/fs2siz.c    |   29 ++++++++++++++++++++
 arch/nds32/math-emu/fs2ui.c     |   29 ++++++++++++++++++++
 arch/nds32/math-emu/fs2uiz.c    |   30 ++++++++++++++++++++
 arch/nds32/math-emu/fsi2d.c     |   22 +++++++++++++++
 arch/nds32/math-emu/fsi2s.c     |   22 +++++++++++++++
 arch/nds32/math-emu/fui2d.c     |   22 +++++++++++++++
 arch/nds32/math-emu/fui2s.c     |   22 +++++++++++++++
 15 files changed, 394 insertions(+), 5 deletions(-)
 create mode 100644 arch/nds32/math-emu/fd2si.c
 create mode 100644 arch/nds32/math-emu/fd2siz.c
 create mode 100644 arch/nds32/math-emu/fd2ui.c
 create mode 100644 arch/nds32/math-emu/fd2uiz.c
 create mode 100644 arch/nds32/math-emu/fs2si.c
 create mode 100644 arch/nds32/math-emu/fs2siz.c
 create mode 100644 arch/nds32/math-emu/fs2ui.c
 create mode 100644 arch/nds32/math-emu/fs2uiz.c
 create mode 100644 arch/nds32/math-emu/fsi2d.c
 create mode 100644 arch/nds32/math-emu/fsi2s.c
 create mode 100644 arch/nds32/math-emu/fui2d.c
 create mode 100644 arch/nds32/math-emu/fui2s.c

diff --git a/arch/nds32/include/asm/fpuemu.h b/arch/nds32/include/asm/fpuemu.h
index c4bd0c7..63e7ef5 100644
--- a/arch/nds32/include/asm/fpuemu.h
+++ b/arch/nds32/include/asm/fpuemu.h
@@ -13,6 +13,12 @@
 void fmuls(void *ft, void *fa, void *fb);
 void fdivs(void *ft, void *fa, void *fb);
 void fs2d(void *ft, void *fa);
+void fs2si(void *ft, void *fa);
+void fs2si_z(void *ft, void *fa);
+void fs2ui(void *ft, void *fa);
+void fs2ui_z(void *ft, void *fa);
+void fsi2s(void *ft, void *fa);
+void fui2s(void *ft, void *fa);
 void fsqrts(void *ft, void *fa);
 void fnegs(void *ft, void *fa);
 int fcmps(void *ft, void *fa, void *fb, int cop);
@@ -26,6 +32,12 @@
 void fdivd(void *ft, void *fa, void *fb);
 void fsqrtd(void *ft, void *fa);
 void fd2s(void *ft, void *fa);
+void fd2si(void *ft, void *fa);
+void fd2si_z(void *ft, void *fa);
+void fd2ui(void *ft, void *fa);
+void fd2ui_z(void *ft, void *fa);
+void fsi2d(void *ft, void *fa);
+void fui2d(void *ft, void *fa);
 void fnegd(void *ft, void *fa);
 int fcmpd(void *ft, void *fa, void *fb, int cop);
 
diff --git a/arch/nds32/math-emu/Makefile b/arch/nds32/math-emu/Makefile
index 947fe0c..e7a746d 100644
--- a/arch/nds32/math-emu/Makefile
+++ b/arch/nds32/math-emu/Makefile
@@ -4,4 +4,7 @@
 
 obj-y	:= fpuemu.o \
 	   fdivd.o fmuld.o fsubd.o faddd.o fs2d.o fsqrtd.o fcmpd.o fnegs.o \
-	   fdivs.o fmuls.o fsubs.o fadds.o fd2s.o fsqrts.o fcmps.o fnegd.o
+	   fd2si.o fd2ui.o fd2siz.o fd2uiz.o fsi2d.o fui2d.o \
+	   fdivs.o fmuls.o fsubs.o fadds.o fd2s.o fsqrts.o fcmps.o fnegd.o \
+	   fs2si.o fs2ui.o fs2siz.o fs2uiz.o fsi2s.o fui2s.o
+
diff --git a/arch/nds32/math-emu/fd2si.c b/arch/nds32/math-emu/fd2si.c
new file mode 100644
index 0000000..fae3e16
--- /dev/null
+++ b/arch/nds32/math-emu/fd2si.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/double.h>
+
+void fd2si(void *ft, void *fa)
+{
+	int r;
+
+	FP_DECL_D(A);
+	FP_DECL_EX;
+
+	FP_UNPACK_DP(A, fa);
+
+	if (A_c == FP_CLS_INF) {
+		*(int *)ft = (A_s == 0) ? 0x7fffffff : 0x80000000;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else if (A_c == FP_CLS_NAN) {
+		*(int *)ft = 0xffffffff;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else {
+		FP_TO_INT_ROUND_D(r, A, 32, 1);
+		__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+		*(int *)ft = r;
+	}
+
+}
diff --git a/arch/nds32/math-emu/fd2siz.c b/arch/nds32/math-emu/fd2siz.c
new file mode 100644
index 0000000..92fe677
--- /dev/null
+++ b/arch/nds32/math-emu/fd2siz.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/double.h>
+
+void fd2si_z(void *ft, void *fa)
+{
+	int r;
+
+	FP_DECL_D(A);
+	FP_DECL_EX;
+
+	FP_UNPACK_DP(A, fa);
+
+	if (A_c == FP_CLS_INF) {
+		*(int *)ft = (A_s == 0) ? 0x7fffffff : 0x80000000;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else if (A_c == FP_CLS_NAN) {
+		*(int *)ft = 0xffffffff;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else {
+		FP_TO_INT_D(r, A, 32, 1);
+		__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+		*(int *)ft = r;
+	}
+
+}
diff --git a/arch/nds32/math-emu/fd2ui.c b/arch/nds32/math-emu/fd2ui.c
new file mode 100644
index 0000000..a0423b6
--- /dev/null
+++ b/arch/nds32/math-emu/fd2ui.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/double.h>
+
+void fd2ui(void *ft, void *fa)
+{
+	unsigned int r;
+
+	FP_DECL_D(A);
+	FP_DECL_EX;
+
+	FP_UNPACK_DP(A, fa);
+
+	if (A_c == FP_CLS_INF) {
+		*(unsigned int *)ft = (A_s == 0) ? 0xffffffff : 0x00000000;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else if (A_c == FP_CLS_NAN) {
+		*(unsigned int *)ft = 0xffffffff;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else {
+		FP_TO_INT_ROUND_D(r, A, 32, 0);
+		__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+		*(unsigned int *)ft = r;
+	}
+
+}
diff --git a/arch/nds32/math-emu/fd2uiz.c b/arch/nds32/math-emu/fd2uiz.c
new file mode 100644
index 0000000..8ae17cf
--- /dev/null
+++ b/arch/nds32/math-emu/fd2uiz.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/double.h>
+
+void fd2ui_z(void *ft, void *fa)
+{
+	unsigned int r;
+
+	FP_DECL_D(A);
+	FP_DECL_EX;
+
+	FP_UNPACK_DP(A, fa);
+
+	if (A_c == FP_CLS_INF) {
+		*(unsigned int *)ft = (A_s == 0) ? 0xffffffff : 0x00000000;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else if (A_c == FP_CLS_NAN) {
+		*(unsigned int *)ft = 0xffffffff;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else {
+		FP_TO_INT_D(r, A, 32, 0);
+		__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+		*(unsigned int *)ft = r;
+	}
+
+}
diff --git a/arch/nds32/math-emu/fpuemu.c b/arch/nds32/math-emu/fpuemu.c
index 75cf164..46558a1 100644
--- a/arch/nds32/math-emu/fpuemu.c
+++ b/arch/nds32/math-emu/fpuemu.c
@@ -113,6 +113,30 @@ static int fpu_emu(struct fpu_struct *fpu_reg, unsigned long insn)
 					func.b = fs2d;
 					ftype = S1D;
 					break;
+				case fs2si_op:
+					func.b = fs2si;
+					ftype = S1S;
+					break;
+				case fs2si_z_op:
+					func.b = fs2si_z;
+					ftype = S1S;
+					break;
+				case fs2ui_op:
+					func.b = fs2ui;
+					ftype = S1S;
+					break;
+				case fs2ui_z_op:
+					func.b = fs2ui_z;
+					ftype = S1S;
+					break;
+				case fsi2s_op:
+					func.b = fsi2s;
+					ftype = S1S;
+					break;
+				case fui2s_op:
+					func.b = fui2s;
+					ftype = S1S;
+					break;
 				case fsqrts_op:
 					func.b = fsqrts;
 					ftype = S1S;
@@ -182,6 +206,30 @@ static int fpu_emu(struct fpu_struct *fpu_reg, unsigned long insn)
 					func.b = fd2s;
 					ftype = D1S;
 					break;
+				case fd2si_op:
+					func.b = fd2si;
+					ftype = D1S;
+					break;
+				case fd2si_z_op:
+					func.b = fd2si_z;
+					ftype = D1S;
+					break;
+				case fd2ui_op:
+					func.b = fd2ui;
+					ftype = D1S;
+					break;
+				case fd2ui_z_op:
+					func.b = fd2ui_z;
+					ftype = D1S;
+					break;
+				case fsi2d_op:
+					func.b = fsi2d;
+					ftype = D1S;
+					break;
+				case fui2d_op:
+					func.b = fui2d;
+					ftype = D1S;
+					break;
 				case fsqrtd_op:
 					func.b = fsqrtd;
 					ftype = D1D;
@@ -305,16 +353,16 @@ static int fpu_emu(struct fpu_struct *fpu_reg, unsigned long insn)
 	 * If an exception is required, generate a tidy SIGFPE exception.
 	 */
 #if IS_ENABLED(CONFIG_SUPPORT_DENORMAL_ARITHMETIC)
-	if (((fpu_reg->fpcsr << 5) & fpu_reg->fpcsr & FPCSR_mskALLE_NO_UDFE) ||
-	    ((fpu_reg->fpcsr & FPCSR_mskUDF) && (fpu_reg->UDF_trap)))
+	if (((fpu_reg->fpcsr << 5) & fpu_reg->fpcsr & FPCSR_mskALLE_NO_UDF_IEXE)
+	    || ((fpu_reg->fpcsr << 5) & (fpu_reg->UDF_IEX_trap))) {
 #else
-	if ((fpu_reg->fpcsr << 5) & fpu_reg->fpcsr & FPCSR_mskALLE)
+	if ((fpu_reg->fpcsr << 5) & fpu_reg->fpcsr & FPCSR_mskALLE) {
 #endif
 		return SIGFPE;
+	}
 	return 0;
 }
 
-
 int do_fpuemu(struct pt_regs *regs, struct fpu_struct *fpu)
 {
 	unsigned long insn = 0, addr = regs->ipc;
@@ -336,6 +384,7 @@ int do_fpuemu(struct pt_regs *regs, struct fpu_struct *fpu)
 
 	if (NDS32Insn_OPCODE(insn) != cop0_op)
 		return SIGILL;
+
 	switch (NDS32Insn_OPCODE_COP0(insn)) {
 	case fs1_op:
 	case fs2_op:
diff --git a/arch/nds32/math-emu/fs2si.c b/arch/nds32/math-emu/fs2si.c
new file mode 100644
index 0000000..b4931d6
--- /dev/null
+++ b/arch/nds32/math-emu/fs2si.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/single.h>
+
+void fs2si(void *ft, void *fa)
+{
+	int r;
+
+	FP_DECL_S(A);
+	FP_DECL_EX;
+
+	FP_UNPACK_SP(A, fa);
+
+	if (A_c == FP_CLS_INF) {
+		*(int *)ft = (A_s == 0) ? 0x7fffffff : 0x80000000;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else if (A_c == FP_CLS_NAN) {
+		*(int *)ft = 0xffffffff;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else {
+		FP_TO_INT_ROUND_S(r, A, 32, 1);
+		__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+		*(int *)ft = r;
+	}
+}
diff --git a/arch/nds32/math-emu/fs2siz.c b/arch/nds32/math-emu/fs2siz.c
new file mode 100644
index 0000000..1c2b99c
--- /dev/null
+++ b/arch/nds32/math-emu/fs2siz.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/single.h>
+
+void fs2si_z(void *ft, void *fa)
+{
+	int r;
+
+	FP_DECL_S(A);
+	FP_DECL_EX;
+
+	FP_UNPACK_SP(A, fa);
+
+	if (A_c == FP_CLS_INF) {
+		*(int *)ft = (A_s == 0) ? 0x7fffffff : 0x80000000;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else if (A_c == FP_CLS_NAN) {
+		*(int *)ft = 0xffffffff;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else {
+		FP_TO_INT_S(r, A, 32, 1);
+		__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+		*(int *)ft = r;
+	}
+}
diff --git a/arch/nds32/math-emu/fs2ui.c b/arch/nds32/math-emu/fs2ui.c
new file mode 100644
index 0000000..c337f03
--- /dev/null
+++ b/arch/nds32/math-emu/fs2ui.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/single.h>
+
+void fs2ui(void *ft, void *fa)
+{
+	unsigned int r;
+
+	FP_DECL_S(A);
+	FP_DECL_EX;
+
+	FP_UNPACK_SP(A, fa);
+
+	if (A_c == FP_CLS_INF) {
+		*(unsigned int *)ft = (A_s == 0) ? 0xffffffff : 0x00000000;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else if (A_c == FP_CLS_NAN) {
+		*(unsigned int *)ft = 0xffffffff;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else {
+		FP_TO_INT_ROUND_S(r, A, 32, 0);
+		__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+		*(unsigned int *)ft = r;
+	}
+}
diff --git a/arch/nds32/math-emu/fs2uiz.c b/arch/nds32/math-emu/fs2uiz.c
new file mode 100644
index 0000000..22c5e47
--- /dev/null
+++ b/arch/nds32/math-emu/fs2uiz.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/single.h>
+
+void fs2ui_z(void *ft, void *fa)
+{
+	unsigned int r;
+
+	FP_DECL_S(A);
+	FP_DECL_EX;
+
+	FP_UNPACK_SP(A, fa);
+
+	if (A_c == FP_CLS_INF) {
+		*(unsigned int *)ft = (A_s == 0) ? 0xffffffff : 0x00000000;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else if (A_c == FP_CLS_NAN) {
+		*(unsigned int *)ft = 0xffffffff;
+		__FPU_FPCSR |= FP_EX_INVALID;
+	} else {
+		FP_TO_INT_S(r, A, 32, 0);
+		__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+		*(unsigned int *)ft = r;
+	}
+
+}
diff --git a/arch/nds32/math-emu/fsi2d.c b/arch/nds32/math-emu/fsi2d.c
new file mode 100644
index 0000000..6b04cec
--- /dev/null
+++ b/arch/nds32/math-emu/fsi2d.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/double.h>
+
+void fsi2d(void *ft, void *fa)
+{
+	int a = *(int *)fa;
+
+	FP_DECL_D(R);
+	FP_DECL_EX;
+
+	FP_FROM_INT_D(R, a, 32, int);
+
+	FP_PACK_DP(ft, R);
+
+	__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+
+}
diff --git a/arch/nds32/math-emu/fsi2s.c b/arch/nds32/math-emu/fsi2s.c
new file mode 100644
index 0000000..689864a
--- /dev/null
+++ b/arch/nds32/math-emu/fsi2s.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/single.h>
+
+void fsi2s(void *ft, void *fa)
+{
+	int a = *(int *)fa;
+
+	FP_DECL_S(R);
+	FP_DECL_EX;
+
+	FP_FROM_INT_S(R, a, 32, int);
+
+	FP_PACK_SP(ft, R);
+
+	__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+
+}
diff --git a/arch/nds32/math-emu/fui2d.c b/arch/nds32/math-emu/fui2d.c
new file mode 100644
index 0000000..9689d33
--- /dev/null
+++ b/arch/nds32/math-emu/fui2d.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/double.h>
+
+void fui2d(void *ft, void *fa)
+{
+	unsigned int a = *(unsigned int *)fa;
+
+	FP_DECL_D(R);
+	FP_DECL_EX;
+
+	FP_FROM_INT_D(R, a, 32, int);
+
+	FP_PACK_DP(ft, R);
+
+	__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+
+}
diff --git a/arch/nds32/math-emu/fui2s.c b/arch/nds32/math-emu/fui2s.c
new file mode 100644
index 0000000..f70f076
--- /dev/null
+++ b/arch/nds32/math-emu/fui2s.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2019 Andes Technology Corporation
+#include <linux/uaccess.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/soft-fp.h>
+#include <math-emu/single.h>
+
+void fui2s(void *ft, void *fa)
+{
+	unsigned int a = *(unsigned int *)fa;
+
+	FP_DECL_S(R);
+	FP_DECL_EX;
+
+	FP_FROM_INT_S(R, a, 32, int);
+
+	FP_PACK_SP(ft, R);
+
+	__FPU_FPCSR |= FP_CUR_EXCEPTIONS;
+
+}
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread
* [PATCH v2 3/3] math-emu: Use statement expressions to fix Wshift-count-overflow warning
  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 ` [PATCH v2 1/3] nds32: Avoid IEX status being incorrectly modified 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
  2 siblings, 0 replies; 4+ messages in thread
From: Vincent Chen @ 2019-05-27  6:17 UTC (permalink / raw)
  To: linux-kernel, arnd, linux-arch, greentime, green.hu, deanbo422; +Cc: vincentc

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


^ permalink raw reply related	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2019-05-27  6:17 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
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 ` [PATCH v2 1/3] nds32: Avoid IEX status being incorrectly modified 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 ` [PATCH v2 3/3] math-emu: Use statement expressions to fix Wshift-count-overflow warning Vincent Chen

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).