[X86] Add test case for pr40539. NFC

llvm-svn: 352697

1 files changed, 36 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/X86/pr40539.ll b/llvm/test/CodeGen/X86/pr40539.ll
new file mode 100644
index 00000000000..65693215daa
--- /dev/null
+++ b/llvm/test/CodeGen/X86/pr40539.ll
@@ -0,0 +1,36 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=i686-unknown-unknown -mcpu=pentium4 | FileCheck %s
+
+; FIXME: The fstps in the following test case should be between the inline
+; assembly expansion and the cmpeqss. The postRA scheduler has rearranged them.
+
+@f1 = global float 1.000000e+00, align 4
+
+define zeroext i1 @_Z9test_log2v() {
+; CHECK-LABEL: _Z9test_log2v:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    pushl %eax
+; CHECK-NEXT:    .cfi_def_cfa_offset 8
+; CHECK-NEXT:    flds f1
+; CHECK-NEXT:    fstps (%esp)
+; CHECK-NEXT:    xorps %xmm0, %xmm0
+; CHECK-NEXT:    #APP
+; CHECK-NEXT:    fld1
+; CHECK-NEXT:    fxch %st(1)
+; CHECK-NEXT:    fyl2x
+; CHECK-NEXT:    #NO_APP
+; CHECK-NEXT:    cmpeqss (%esp), %xmm0
+; CHECK-NEXT:    movd %xmm0, %eax
+; CHECK-NEXT:    andl $1, %eax
+; CHECK-NEXT:    # kill: def $al killed $al killed $eax
+; CHECK-NEXT:    popl %ecx
+; CHECK-NEXT:    .cfi_def_cfa_offset 4
+; CHECK-NEXT:    retl
+entry:
+  %0 = load float, float* @f1, align 4
+  %1 = fpext float %0 to x86_fp80
+  %2 = tail call x86_fp80 asm "fld1; fxch; fyl2x", "={st},0,~{st(1)},~{dirflag},~{fpsr},~{flags}"(x86_fp80 %1)
+  %conv = fptrunc x86_fp80 %2 to float
+  %3 = fcmp oeq float %conv, 0.000000e+00
+  ret i1 %3
+}