1 files changed, 51 insertions, 0 deletions
diff --git a/test/CodeGen/X86/pre-coalesce.ll b/test/CodeGen/X86/pre-coalesce.ll
new file mode 100644
index 0000000000000..9cd6365453c92
--- /dev/null
+++ b/test/CodeGen/X86/pre-coalesce.ll
@@ -0,0 +1,51 @@
+; RUN: llc -regalloc=greedy -mtriple=x86_64-unknown-linux-gnu  < %s -o - | FileCheck %s
+;
+; The test is to check no redundent mov as follows will be generated in %while.body loop.
+;  .LBB0_2:
+;    movsbl	%cl, %ecx
+;    movl	%edx, %eax   ==> This movl can be promoted outside of loop.
+;    shll	$5, %eax
+;    ...
+;    movl	%eax, %edx
+;    jne     .LBB0_2
+;
+; CHECK-LABEL: foo:
+; CHECK: [[L0:.LBB0_[0-9]+]]: # %while.body
+; CHECK: movl %[[REGA:.*]], %[[REGB:.*]]
+; CHECK-NOT: movl %[[REGB]], %[[REGA]]
+; CHECK: jne [[L0]]
+;
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+@b = common local_unnamed_addr global i8* null, align 8
+@a = common local_unnamed_addr global i32 0, align 4
+
+define i32 @foo() local_unnamed_addr {
+entry:
+  %t0 = load i8*, i8** @b, align 8
+  %t1 = load i8, i8* %t0, align 1
+  %cmp4 = icmp eq i8 %t1, 0
+  %t2 = load i32, i32* @a, align 4
+  br i1 %cmp4, label %while.end, label %while.body.preheader
+
+while.body.preheader:                             ; preds = %entry
+  br label %while.body
+
+while.body:                                       ; preds = %while.body.preheader, %while.body
+  %t3 = phi i32 [ %add3, %while.body ], [ %t2, %while.body.preheader ]
+  %t4 = phi i8 [ %t5, %while.body ], [ %t1, %while.body.preheader ]
+  %conv = sext i8 %t4 to i32
+  %add = mul i32 %t3, 33
+  %add3 = add nsw i32 %add, %conv
+  store i32 %add3, i32* @a, align 4
+  %t5 = load i8, i8* %t0, align 1
+  %cmp = icmp eq i8 %t5, 0
+  br i1 %cmp, label %while.end.loopexit, label %while.body
+
+while.end.loopexit:                               ; preds = %while.body
+  br label %while.end
+
+while.end:                                        ; preds = %while.end.loopexit, %entry
+  %.lcssa = phi i32 [ %t2, %entry ], [ %add3, %while.end.loopexit ]
+  ret i32 %.lcssa
+}