[Hexagon] Generate multiply-high instruction in isel

llvm-svn: 305302
diff --git a/llvm/test/CodeGen/Hexagon/mulh.ll b/llvm/test/CodeGen/Hexagon/mulh.ll
new file mode 100644
index 0000000..0442e28
--- /dev/null
+++ b/llvm/test/CodeGen/Hexagon/mulh.ll
@@ -0,0 +1,27 @@
+; RUN: llc -march=hexagon < %s | FileCheck %s
+
+target triple = "hexagon"
+
+; CHECK-LABEL: danny:
+; CHECK: r{{[0-9]+}} = mpy(r0,r1)  
+define i32 @danny(i32 %a0, i32 %a1) {
+b2:
+  %v3 = sext i32 %a0 to i64
+  %v4 = sext i32 %a1 to i64
+  %v5 = mul nsw i64 %v3, %v4
+  %v6 = ashr i64 %v5, 32
+  %v7 = trunc i64 %v6 to i32
+  ret i32 %v7
+}
+
+; CHECK-LABEL: sammy:
+; CHECK: r{{[0-9]+}} = mpy(r0,r1)
+define i32 @sammy(i32 %a0, i32 %a1) {
+b2:
+  %v3 = sext i32 %a0 to i64
+  %v4 = sext i32 %a1 to i64
+  %v5 = mul nsw i64 %v3, %v4
+  %v6 = lshr i64 %v5, 32
+  %v7 = trunc i64 %v6 to i32
+  ret i32 %v7
+}