Lower multiply with overflow checking to __mulo<mode>

calls if we haven't been able to lower them any
other way.

Fixes rdar://9090077 and rdar://9210061


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133288 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGen/X86/muloti.ll

@@ -0,0 +1,38 @@
+; RUN: llc < %s -mtriple=x86_64-apple-darwin | FileCheck %s
+%0 = type { i64, i64 }
+%1 = type { i128, i1 }
+
+@.str = private unnamed_addr constant [11 x i8] c"%llx %llx\0A\00", align 1
+
+define %0 @x(i64 %a.coerce0, i64 %a.coerce1, i64 %b.coerce0, i64 %b.coerce1) nounwind uwtable ssp {
+entry:
+  %tmp16 = zext i64 %a.coerce0 to i128
+  %tmp11 = zext i64 %a.coerce1 to i128
+  %tmp12 = shl nuw i128 %tmp11, 64
+  %ins14 = or i128 %tmp12, %tmp16
+  %tmp6 = zext i64 %b.coerce0 to i128
+  %tmp3 = zext i64 %b.coerce1 to i128
+  %tmp4 = shl nuw i128 %tmp3, 64
+  %ins = or i128 %tmp4, %tmp6
+  %0 = tail call %1 @llvm.smul.with.overflow.i128(i128 %ins14, i128 %ins)
+; CHECK: callq   ___muloti4
+  %1 = extractvalue %1 %0, 0
+  %2 = extractvalue %1 %0, 1
+  br i1 %2, label %overflow, label %nooverflow
+
+overflow:                                         ; preds = %entry
+  tail call void @llvm.trap()
+  unreachable
+
+nooverflow:                                       ; preds = %entry
+  %tmp20 = trunc i128 %1 to i64
+  %tmp21 = insertvalue %0 undef, i64 %tmp20, 0
+  %tmp22 = lshr i128 %1, 64
+  %tmp23 = trunc i128 %tmp22 to i64
+  %tmp24 = insertvalue %0 %tmp21, i64 %tmp23, 1
+  ret %0 %tmp24
+}
+
+declare %1 @llvm.smul.with.overflow.i128(i128, i128) nounwind readnone
+
+declare void @llvm.trap() nounwind