[Hexagon] Pick the right branch opcode depending on branch probabilities

Specifically, pick the opcode with the correct branch prediction, i.e.
jump:t or jump:nt.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296821 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 44 insertions, 0 deletions

diff --git a/test/CodeGen/Hexagon/builtin-expect.ll b/test/CodeGen/Hexagon/builtin-expect.ll
new file mode 100644
index 00000000000..9945da1782b
--- /dev/null
+++ b/test/CodeGen/Hexagon/builtin-expect.ll
@@ -0,0 +1,44 @@
+; RUN: llc -march=hexagon -disable-block-placement < %s | FileCheck %s
+
+; Check that the branch to the block b10 is marked as taken (i.e. ":t").
+; CHECK-LABEL: foo
+; CHECK: if ({{.*}}) jump:t .LBB0_[[LAB:[0-9]+]]
+; CHECK: [[LAB]]:
+; CHECK: add({{.*}},#65)
+
+target triple = "hexagon"
+
+define i32 @foo(i32 %a0) local_unnamed_addr #0 {
+b1:
+  %v2 = icmp eq i32 %a0, 0
+  br i1 %v2, label %b3, label %b10, !prof !0
+
+b3:                                               ; preds = %b1
+  br label %b4
+
+b4:                                               ; preds = %b4, %b3
+  %v5 = phi i32 [ %v6, %b4 ], [ 0, %b3 ]
+  %v6 = add nuw nsw i32 %v5, 1
+  %v7 = mul nuw nsw i32 %v5, 67
+  %v8 = tail call i32 @bar(i32 %v7) #0
+  %v9 = icmp eq i32 %v6, 10
+  br i1 %v9, label %b13, label %b4
+
+b10:                                              ; preds = %b1
+  %v11 = add nsw i32 %a0, 65
+  %v12 = tail call i32 @bar(i32 %v11) #0
+  br label %b14
+
+b13:                                              ; preds = %b4
+  br label %b14
+
+b14:                                              ; preds = %b13, %b10
+  %v15 = phi i32 [ %v12, %b10 ], [ 0, %b13 ]
+  ret i32 %v15
+}
+
+declare i32 @bar(i32) local_unnamed_addr #0
+
+attributes #0 = { nounwind "target-cpu"="hexagonv60" "target-features"="+hvx,-hvx-double,-long-calls" }
+
+!0 = !{!"branch_weights", i32 1, i32 2000}