Add target-specific dag combines for FAND(x,0) and FOR(x,0). This allows
us to compile:
double test(double X) {
return copysign(0.0, X);
}
into:
_test:
andpd LCPI1_0(%rip), %xmm0
ret
instead of:
_test:
pxor %xmm1, %xmm1
andpd LCPI1_0(%rip), %xmm1
movapd %xmm0, %xmm2
andpd LCPI1_1(%rip), %xmm2
movapd %xmm1, %xmm0
orpd %xmm2, %xmm0
ret
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46344 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/X86/copysign-zero.ll b/test/CodeGen/X86/copysign-zero.ll
new file mode 100644
index 0000000..a08fa65
--- /dev/null
+++ b/test/CodeGen/X86/copysign-zero.ll
@@ -0,0 +1,14 @@
+; RUN: llvm-as < %s | llc | not grep orpd
+; RUN: llvm-as < %s | llc | grep andpd | count 1
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"
+target triple = "x86_64-apple-darwin8"
+
+define double @test(double %X) nounwind {
+entry:
+ %tmp2 = tail call double @copysign( double 0.000000e+00, double %X ) nounwind readnone ; <double> [#uses=1]
+ ret double %tmp2
+}
+
+declare double @copysign(double, double) nounwind readnone
+