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authorStephen Hines <srhines@google.com>2014-05-29 02:49:00 -0700
committerStephen Hines <srhines@google.com>2014-05-29 02:49:00 -0700
commitdce4a407a24b04eebc6a376f8e62b41aaa7b071f (patch)
treedcebc53f2b182f145a2e659393bf9a0472cedf23 /test/CodeGen/X86/constant-hoisting-shift-immediate.ll
parent220b921aed042f9e520c26cffd8282a94c66c3d5 (diff)
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Update LLVM for 3.5 rebase (r209712).
Change-Id: I149556c940fb7dc92d075273c87ff584f400941f
Diffstat (limited to 'test/CodeGen/X86/constant-hoisting-shift-immediate.ll')
-rw-r--r--test/CodeGen/X86/constant-hoisting-shift-immediate.ll25
1 files changed, 25 insertions, 0 deletions
diff --git a/test/CodeGen/X86/constant-hoisting-shift-immediate.ll b/test/CodeGen/X86/constant-hoisting-shift-immediate.ll
new file mode 100644
index 0000000..883be35
--- /dev/null
+++ b/test/CodeGen/X86/constant-hoisting-shift-immediate.ll
@@ -0,0 +1,25 @@
+; RUN: llc < %s -O3 -march=x86-64 |FileCheck %s
+define i64 @foo(i1 %z, i192* %p, i192* %q)
+{
+; If const 128 is hoisted to a variable, then in basic block L_val2 we would
+; have %lshr2 = lshr i192 %data2, %const, and the definition of %const would
+; be in another basic block. As a result, a very inefficient code might be
+; produced. Here we check that this doesn't occur.
+entry:
+ %data1 = load i192* %p, align 8
+ %lshr1 = lshr i192 %data1, 128
+ %val1 = trunc i192 %lshr1 to i64
+ br i1 %z, label %End, label %L_val2
+
+; CHECK: movq 16(%rdx), %rax
+; CHECK-NEXT: retq
+L_val2:
+ %data2 = load i192* %q, align 8
+ %lshr2 = lshr i192 %data2, 128
+ %val2 = trunc i192 %lshr2 to i64
+ br label %End
+
+End:
+ %p1 = phi i64 [%val1,%entry], [%val2,%L_val2]
+ ret i64 %p1
+}