commit b6c7f6e5950e609a2ede7990d2be0a1d1b55304f
author Elliott Hughes <enh@google.com> Fri Nov 03 16:46:32 2017 -0700
committer Elliott Hughes <enh@google.com> Fri Nov 03 16:46:32 2017 -0700
tree 3c68573b1d47c41b8a5e2102ec8295ff3f88f29c
parent b06bb71672094d18d928c19ddc631af07931431f

Fix arm/arm64 <fenv.h> to match current reality.

ARM stopped supporting enabling of FP exceptions years ago.

Bug: http://b/68832485
Test: ran tests
Change-Id: I8450baa78e04d994c352180975b0a1ecd5a9f662

libc/include/android/legacy_fenv_inlines_arm.h

diff --git a/libc/include/android/legacy_fenv_inlines_arm.h b/libc/include/android/legacy_fenv_inlines_arm.h
index 58c49c2..de024cf 100644
--- a/libc/include/android/legacy_fenv_inlines_arm.h
+++ b/libc/include/android/legacy_fenv_inlines_arm.h
@@ -35,9 +35,6 @@
 
 __BEGIN_DECLS
 
-#define FPSCR_ENABLE_SHIFT 8
-#define FPSCR_ENABLE_MASK  (FE_ALL_EXCEPT << FPSCR_ENABLE_SHIFT)
-
 #define FPSCR_RMODE_SHIFT 22
 
 static __inline int fegetenv(fenv_t* __envp) {
@@ -108,7 +105,7 @@
   fenv_t __env;
   fegetenv(&__env);
   *__envp = __env;
-  __env &= ~(FE_ALL_EXCEPT | FPSCR_ENABLE_MASK);
+  __env &= ~FE_ALL_EXCEPT;
   fesetenv(&__env);
   return 0;
 }
@@ -121,30 +118,18 @@
   return 0;
 }
 
-static __inline int feenableexcept(int __mask) {
-  fenv_t __old_fpscr, __new_fpscr;
-  fegetenv(&__old_fpscr);
-  __new_fpscr = __old_fpscr | (__mask & FE_ALL_EXCEPT) << FPSCR_ENABLE_SHIFT;
-  fesetenv(&__new_fpscr);
-  return ((__old_fpscr >> FPSCR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
+static __inline int feenableexcept(int __mask __unused) {
+  return -1;
 }
 
-static __inline int fedisableexcept(int __mask) {
-  fenv_t __old_fpscr, __new_fpscr;
-  fegetenv(&__old_fpscr);
-  __new_fpscr = __old_fpscr & ~((__mask & FE_ALL_EXCEPT) << FPSCR_ENABLE_SHIFT);
-  fesetenv(&__new_fpscr);
-  return ((__old_fpscr >> FPSCR_ENABLE_SHIFT) & FE_ALL_EXCEPT);
+static __inline int fedisableexcept(int __mask __unused) {
+  return 0;
 }
 
 static __inline int fegetexcept(void) {
-  fenv_t __fpscr;
-  fegetenv(&__fpscr);
-  return ((__fpscr & FPSCR_ENABLE_MASK) >> FPSCR_ENABLE_SHIFT);
+  return 0;
 }
 
-#undef FPSCR_ENABLE_SHIFT
-#undef FPSCR_ENABLE_MASK
 #undef FPSCR_RMODE_SHIFT
 
 __END_DECLS