Generalize LSR's OptimizeMax to handle the new kinds of max expressions

that indvars may use, now that indvars is recognizing le and ge loops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102235 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 32 insertions, 0 deletions

diff --git a/test/CodeGen/X86/optimize-max-3.ll b/test/CodeGen/X86/optimize-max-3.ll
new file mode 100644
index 0000000000..bf8bfa28da
--- /dev/null
+++ b/test/CodeGen/X86/optimize-max-3.ll
@@ -0,0 +1,32 @@
+; RUN: llc < %s -march=x86-64 | FileCheck %s
+
+; LSR's OptimizeMax should eliminate the select (max).
+
+; CHECK: foo:
+; CHECK-NOT: cmov
+; CHECK: jle
+
+define void @foo(i64 %n, double* nocapture %p) nounwind {
+entry:
+  %cmp6 = icmp slt i64 %n, 0                      ; <i1> [#uses=1]
+  br i1 %cmp6, label %for.end, label %for.body.preheader
+
+for.body.preheader:                               ; preds = %entry
+  %tmp = icmp sgt i64 %n, 0                       ; <i1> [#uses=1]
+  %n.op = add i64 %n, 1                           ; <i64> [#uses=1]
+  %tmp1 = select i1 %tmp, i64 %n.op, i64 1        ; <i64> [#uses=1]
+  br label %for.body
+
+for.body:                                         ; preds = %for.body.preheader, %for.body
+  %i = phi i64 [ %i.next, %for.body ], [ 0, %for.body.preheader ] ; <i64> [#uses=2]
+  %arrayidx = getelementptr double* %p, i64 %i    ; <double*> [#uses=2]
+  %t4 = load double* %arrayidx                    ; <double> [#uses=1]
+  %mul = fmul double %t4, 2.200000e+00            ; <double> [#uses=1]
+  store double %mul, double* %arrayidx
+  %i.next = add nsw i64 %i, 1                     ; <i64> [#uses=2]
+  %exitcond = icmp eq i64 %i.next, %tmp1          ; <i1> [#uses=1]
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:                                          ; preds = %for.body, %entry
+  ret void
+}