[src/trunk]: src/sys/arch/sparc64/include The real cause for removing asm inl...

[nakayama <nakayama%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/d213ecfa45eb
branches:  trunk
changeset: 840457:d213ecfa45eb
user:      nakayama <nakayama%NetBSD.org@localhost>
date:      Sat Apr 06 21:40:15 2019 +0000

description:
The real cause for removing asm inline code on clang is that the
"r" constraint cannot handle 64-bit and is treated as 32-bit.

So code that refers to the upper 32-bit (manuf or impl) of the %ver
register is removed by optimization.

Use 32-bit kernel code as a workaround when referring to the %ver
register.

diffstat:

 sys/arch/sparc64/include/psl.h |  19 +++++++++++++------
 1 files changed, 13 insertions(+), 6 deletions(-)

diffs (50 lines):

diff -r 969caa22fb2b -r d213ecfa45eb sys/arch/sparc64/include/psl.h
--- a/sys/arch/sparc64/include/psl.h    Sat Apr 06 20:25:26 2019 +0000
+++ b/sys/arch/sparc64/include/psl.h    Sat Apr 06 21:40:15 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: psl.h,v 1.59 2019/04/05 12:15:41 nakayama Exp $ */
+/*     $NetBSD: psl.h,v 1.60 2019/04/06 21:40:15 nakayama Exp $ */
 
 /*
  * Copyright (c) 1992, 1993
@@ -292,9 +292,8 @@
  * Put "memory" to asm inline on sun4v to avoid issuing rdpr %ver
  * before checking cputyp as a result of code moving by compiler
  * optimization.
- * For clang, to prevent it from being removed by optimization.
  */
-#if defined(SUN4V) || defined(__clang__)
+#ifdef SUN4V
 #define constasm_clobbers "memory"
 #else
 #define constasm_clobbers
@@ -323,11 +322,13 @@
        __asm volatile(#wr " %0,0,%" #reg : : "r" (_val) : "memory");   \
 }
 
-#ifdef __arch64__
+/*
+ * XXX: clang's "r" constraint cannot handle 64-bit,
+ * so use 32-bit kernel code as a workaround.
+ */
+#if defined(__arch64__) && !defined(__clang__)
 #define SPARC64_RDCONST64_DEF(rd, name, reg) \
        SPARC64_RDCONST_DEF(rd, name, reg, uint64_t)
-#define SPARC64_RD64_DEF(rd, name, reg) SPARC64_RD_DEF(rd, name, reg, uint64_t)
-#define SPARC64_WR64_DEF(wr, name, reg) SPARC64_WR_DEF(wr, name, reg, uint64_t)
 #else
 #define SPARC64_RDCONST64_DEF(rd, name, reg)                           \
 static __inline __constfunc uint64_t get##name(void)                   \
@@ -337,6 +338,12 @@
                : "=r" (_hi), "=r" (_lo) : : constasm_clobbers);        \
        return ((uint64_t)_hi << 32) | _lo;                             \
 }
+#endif
+
+#ifdef __arch64__
+#define SPARC64_RD64_DEF(rd, name, reg) SPARC64_RD_DEF(rd, name, reg, uint64_t)
+#define SPARC64_WR64_DEF(wr, name, reg) SPARC64_WR_DEF(wr, name, reg, uint64_t)
+#else
 #define SPARC64_RD64_DEF(rd, name, reg)                                        \
 static __inline uint64_t get##name(void)                               \
 {                                                                      \