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| author | Dan Gohman <gohman@apple.com> | 2010-06-24 02:06:24 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2010-06-24 02:06:24 +0000 |
| commit | 8e0163ac1e8fcf0f8d2340d65439edef8230b01c (patch) | |
| tree | ca54810bf847d0442f8db0df9e16a780276f1a7a /test | |
| parent | b8ac3b035ba14663ebe57fde17f6a9f25134e005 (diff) | |
Optimize the "bit test" code path for switch lowering in the
case where the bit mask has exactly one bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106716 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test')
| -rw-r--r-- | test/CodeGen/X86/switch-bt.ll | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/test/CodeGen/X86/switch-bt.ll b/test/CodeGen/X86/switch-bt.ll new file mode 100644 index 0000000000..ed3266ec42 --- /dev/null +++ b/test/CodeGen/X86/switch-bt.ll @@ -0,0 +1,51 @@ +; RUN: llc -march=x86-64 -asm-verbose=false < %s | FileCheck %s + +; This switch should use bit tests, and the third bit test case is just +; testing for one possible value, so it doesn't need a bt. + +; CHECK: movabsq $2305843009482129440, %r +; CHECK-NEXT: btq %rax, %r +; CHECK-NEXT: jb +; CHECK-NEXT: movl $671088640, %e +; CHECK-NEXT: btq %rax, %r +; CHECK-NEXT: jb +; CHECK-NEXT: testq %rax, %r +; CHECK-NEXT: j + +define void @test(i8* %l) nounwind { +entry: + %l.addr = alloca i8*, align 8 ; <i8**> [#uses=2] + store i8* %l, i8** %l.addr + %tmp = load i8** %l.addr ; <i8*> [#uses=1] + %tmp1 = load i8* %tmp ; <i8> [#uses=1] + %conv = sext i8 %tmp1 to i32 ; <i32> [#uses=1] + switch i32 %conv, label %sw.default [ + i32 62, label %sw.bb + i32 60, label %sw.bb + i32 38, label %sw.bb2 + i32 94, label %sw.bb2 + i32 61, label %sw.bb2 + i32 33, label %sw.bb4 + ] + +sw.bb: ; preds = %entry, %entry + call void @foo(i32 0) + br label %sw.epilog + +sw.bb2: ; preds = %entry, %entry, %entry + call void @foo(i32 1) + br label %sw.epilog + +sw.bb4: ; preds = %entry + call void @foo(i32 3) + br label %sw.epilog + +sw.default: ; preds = %entry + call void @foo(i32 97) + br label %sw.epilog + +sw.epilog: ; preds = %sw.default, %sw.bb4, %sw.bb2, %sw.bb + ret void +} + +declare void @foo(i32) |