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| author | Craig Topper <craig.topper@intel.com> | 2018-08-01 18:38:43 +0000 |
|---|---|---|
| committer | Craig Topper <craig.topper@intel.com> | 2018-08-01 18:38:43 +0000 |
| commit | ffb8eb30ff85d5d2ffbfbebc36b0f2002dc3aa99 (patch) | |
| tree | 99eac15ef21c467223cc8f62ff6266d97a527cf4 | |
| parent | 95d8c464d8ff334e7ceaa1630a6d39a5cb72e69c (diff) | |
| download | bcm5719-llvm-ffb8eb30ff85d5d2ffbfbebc36b0f2002dc3aa99.tar.gz bcm5719-llvm-ffb8eb30ff85d5d2ffbfbebc36b0f2002dc3aa99.zip | |
[X86] Add test cases for the patterns used by __builtin_ffs.
We previously had tests for "__builtin_ffs + 5", but the SelectinoDAG without an extra addition came out slightly different.
llvm-svn: 338612
| -rw-r--r-- | llvm/test/CodeGen/X86/dagcombine-select.ll | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/X86/dagcombine-select.ll b/llvm/test/CodeGen/X86/dagcombine-select.ll index 1ef6cfdfd40..50d2809e008 100644 --- a/llvm/test/CodeGen/X86/dagcombine-select.ll +++ b/llvm/test/CodeGen/X86/dagcombine-select.ll @@ -378,3 +378,52 @@ define i32 @cttz_32_ne_select(i32 %v) nounwind { %add = select i1 %tobool, i32 %.op, i32 5 ret i32 %add } + +; This matches the pattern emitted for __builtin_ffs +define i32 @cttz_32_eq_select_ffs(i32 %v) nounwind { +; NOBMI-LABEL: cttz_32_eq_select_ffs: +; NOBMI: # %bb.0: +; NOBMI-NEXT: bsfl %edi, %eax +; NOBMI-NEXT: incl %eax +; NOBMI-NEXT: testl %edi, %edi +; NOBMI-NEXT: cmovel %edi, %eax +; NOBMI-NEXT: retq +; +; BMI-LABEL: cttz_32_eq_select_ffs: +; BMI: # %bb.0: +; BMI-NEXT: tzcntl %edi, %eax +; BMI-NEXT: incl %eax +; BMI-NEXT: testl %edi, %edi +; BMI-NEXT: cmovel %edi, %eax +; BMI-NEXT: retq + + %cnt = tail call i32 @llvm.cttz.i32(i32 %v, i1 true) + %tobool = icmp eq i32 %v, 0 + %.op = add nuw nsw i32 %cnt, 1 + %add = select i1 %tobool, i32 0, i32 %.op + ret i32 %add +} + +define i32 @cttz_32_ne_select_ffs(i32 %v) nounwind { +; NOBMI-LABEL: cttz_32_ne_select_ffs: +; NOBMI: # %bb.0: +; NOBMI-NEXT: bsfl %edi, %eax +; NOBMI-NEXT: incl %eax +; NOBMI-NEXT: testl %edi, %edi +; NOBMI-NEXT: cmovel %edi, %eax +; NOBMI-NEXT: retq +; +; BMI-LABEL: cttz_32_ne_select_ffs: +; BMI: # %bb.0: +; BMI-NEXT: tzcntl %edi, %eax +; BMI-NEXT: incl %eax +; BMI-NEXT: testl %edi, %edi +; BMI-NEXT: cmovel %edi, %eax +; BMI-NEXT: retq + + %cnt = tail call i32 @llvm.cttz.i32(i32 %v, i1 true) + %tobool = icmp ne i32 %v, 0 + %.op = add nuw nsw i32 %cnt, 1 + %add = select i1 %tobool, i32 %.op, i32 0 + ret i32 %add +} |
