indvars: fixed IV cloning in -disable-iv-rewrite mode with associated

cleanup and overdue test cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132038 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 123 insertions, 0 deletions

diff --git a/test/Transforms/IndVarSimplify/no-iv-rewrite.ll b/test/Transforms/IndVarSimplify/no-iv-rewrite.ll
new file mode 100644
index 0000000..c35feef
--- /dev/null
+++ b/test/Transforms/IndVarSimplify/no-iv-rewrite.ll
@@ -0,0 +1,123 @@
+; RUN: opt < %s -indvars -disable-iv-rewrite -S | FileCheck %s
+;
+; Make sure that indvars isn't inserting canonical IVs.
+; This is kinda hard to do until linear function test replacement is removed.
+
+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-n8:16:32:64"
+
+define i32 @sum(i32* %arr, i32 %n) nounwind {
+entry:
+  %precond = icmp slt i32 0, %n
+  br i1 %precond, label %ph, label %return
+
+ph:
+  br label %loop
+
+; CHECK: loop:
+;
+; We should only have 2 IVs.
+; CHECK: phi
+; CHECK: phi
+; CHECK-NOT: phi
+;
+; sext should be eliminated while preserving gep inboundsness.
+; CHECK-NOT: sext
+; CHECK: getelementptr inbounds
+loop:
+  %i.02 = phi i32 [ 0, %ph ], [ %iinc, %loop ]
+  %s.01 = phi i32 [ 0, %ph ], [ %sinc, %loop ]
+  %ofs = sext i32 %i.02 to i64
+  %adr = getelementptr inbounds i32* %arr, i64 %ofs
+  %val = load i32* %adr
+  %sinc = add nsw i32 %s.01, %val
+  %iinc = add nsw i32 %i.02, 1
+  %cond = icmp slt i32 %iinc, %n
+  br i1 %cond, label %loop, label %exit
+
+exit:
+  %s.lcssa = phi i32 [ %sinc, %loop ]
+  br label %return
+
+return:
+  %s.0.lcssa = phi i32 [ %s.lcssa, %exit ], [ 0, %entry ]
+  ret i32 %s.0.lcssa
+}
+
+define i64 @suml(i32* %arr, i32 %n) nounwind {
+entry:
+  %precond = icmp slt i32 0, %n
+  br i1 %precond, label %ph, label %return
+
+ph:
+  br label %loop
+
+; CHECK: loop:
+;
+; We should only have 2 IVs.
+; CHECK: phi
+; CHECK: phi
+; CHECK-NOT: phi
+;
+; %ofs sext should be eliminated while preserving gep inboundsness.
+; CHECK-NOT: sext
+; CHECK: getelementptr inbounds
+; %vall sext should obviously not be eliminated
+; CHECK: sext
+loop:
+  %i.02 = phi i32 [ 0, %ph ], [ %iinc, %loop ]
+  %s.01 = phi i64 [ 0, %ph ], [ %sinc, %loop ]
+  %ofs = sext i32 %i.02 to i64
+  %adr = getelementptr inbounds i32* %arr, i64 %ofs
+  %val = load i32* %adr
+  %vall = sext i32 %val to i64
+  %sinc = add nsw i64 %s.01, %vall
+  %iinc = add nsw i32 %i.02, 1
+  %cond = icmp slt i32 %iinc, %n
+  br i1 %cond, label %loop, label %exit
+
+exit:
+  %s.lcssa = phi i64 [ %sinc, %loop ]
+  br label %return
+
+return:
+  %s.0.lcssa = phi i64 [ %s.lcssa, %exit ], [ 0, %entry ]
+  ret i64 %s.0.lcssa
+}
+
+define void @outofbounds(i32* %first, i32* %last, i32 %idx) nounwind {
+  %precond = icmp ne i32* %first, %last
+  br i1 %precond, label %ph, label %return
+
+; CHECK: ph:
+; It's not indvars' job to perform LICM on %ofs
+; CHECK-NOT: sext
+ph:
+  br label %loop
+
+; CHECK: loop:
+;
+; Preserve exactly one pointer type IV.
+; CHECK: phi i32*
+; CHECK-NOT: phi
+;
+; Don't create any extra adds.
+; CHECK-NOT: add
+;
+; Preserve gep inboundsness, and don't factor it.
+; CHECK: getelementptr inbounds i32* %ptriv, i32 1
+; CHECK-NOT: add
+loop:
+  %ptriv = phi i32* [ %first, %ph ], [ %ptrpost, %loop ]
+  %ofs = sext i32 %idx to i64
+  %adr = getelementptr inbounds i32* %ptriv, i64 %ofs
+  store i32 3, i32* %adr
+  %ptrpost = getelementptr inbounds i32* %ptriv, i32 1
+  %cond = icmp ne i32* %ptrpost, %last
+  br i1 %cond, label %loop, label %exit
+
+exit:
+  br label %return
+
+return:
+  ret void
+}