diff options
| -rw-r--r-- | lib/Target/X86/README-SSE.txt | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/lib/Target/X86/README-SSE.txt b/lib/Target/X86/README-SSE.txt index aa3405ca33..b4fc53ad0a 100644 --- a/lib/Target/X86/README-SSE.txt +++ b/lib/Target/X86/README-SSE.txt @@ -741,3 +741,18 @@ save, as a really-signed value would be undefined for pslld. //===---------------------------------------------------------------------===// + +#include <math.h> +int t1(double d) { return signbit(d); } + +This currently compiles to: + subl $12, %esp + movsd 16(%esp), %xmm0 + movsd %xmm0, (%esp) + movl 4(%esp), %eax + shrl $31, %eax + addl $12, %esp + ret + +We should use movmskp{s|d} instead. + |