If SSE2 is available, x86 should pass first 3 f32/f64 arguments in XMM registers for fastcc calls.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55840 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86CallingConv.td b/lib/Target/X86/X86CallingConv.td
index 549eb9b..e720b0b 100644
--- a/lib/Target/X86/X86CallingConv.td
+++ b/lib/Target/X86/X86CallingConv.td
@@ -352,6 +352,12 @@
// The first 2 integer arguments are passed in ECX/EDX
CCIfType<[i32], CCAssignToReg<[ECX, EDX]>>,
+ // The first 3 float or double arguments, if the call is not a vararg
+ // call and if SSE2 is available, are passed in SSE registers.
+ CCIfNotVarArg<CCIfType<[f32,f64],
+ CCIfSubtarget<"hasSSE2()",
+ CCAssignToReg<[XMM0,XMM1,XMM2]>>>>,
+
// Doubles get 8-byte slots that are 8-byte aligned.
CCIfType<[f64], CCAssignToStack<8, 8>>,