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| author | Craig Topper <craig.topper@intel.com> | 2019-06-04 17:44:18 +0000 |
|---|---|---|
| committer | Craig Topper <craig.topper@intel.com> | 2019-06-04 17:44:18 +0000 |
| commit | 09a4415803cd590ebb68a5141950366b077f13a7 (patch) | |
| tree | 390cc4a57b56939c33765030b79e1c537f8878a4 /llvm/test/CodeGen/X86/bmi.ll | |
| parent | 0cdaf3a09fea6db0008828264bf84c91a5b6eba1 (diff) | |
| download | bcm5719-llvm-09a4415803cd590ebb68a5141950366b077f13a7.tar.gz bcm5719-llvm-09a4415803cd590ebb68a5141950366b077f13a7.zip | |
[DAGCombiner][X86] Fold (not (neg X)) -> (add X, -1)
This is a special case of a more general transform (not (sub Y, X)) -> (add X, ~Y). InstCombine knows the general form. I've restricted to the special case to fix the motivating case PR42118. I tried handling any case where Y was constant, but got some changes on some Mips tests that I couldn't quickly prove where beneficial.
Fixes PR42118
Differential Revision: https://reviews.llvm.org/D62828
llvm-svn: 362533
Diffstat (limited to 'llvm/test/CodeGen/X86/bmi.ll')
| -rw-r--r-- | llvm/test/CodeGen/X86/bmi.ll | 27 |
1 files changed, 10 insertions, 17 deletions
diff --git a/llvm/test/CodeGen/X86/bmi.ll b/llvm/test/CodeGen/X86/bmi.ll index c48be66705f..c2d13c29710 100644 --- a/llvm/test/CodeGen/X86/bmi.ll +++ b/llvm/test/CodeGen/X86/bmi.ll @@ -1153,10 +1153,7 @@ declare void @bar() define void @pr42118_i32(i32 %x) { ; X86-LABEL: pr42118_i32: ; X86: # %bb.0: -; X86-NEXT: movl {{[0-9]+}}(%esp), %eax -; X86-NEXT: movl %eax, %ecx -; X86-NEXT: negl %ecx -; X86-NEXT: andnl %eax, %ecx, %eax +; X86-NEXT: blsrl {{[0-9]+}}(%esp), %eax ; X86-NEXT: jne .LBB48_1 ; X86-NEXT: # %bb.2: ; X86-NEXT: jmp bar # TAILCALL @@ -1165,9 +1162,7 @@ define void @pr42118_i32(i32 %x) { ; ; X64-LABEL: pr42118_i32: ; X64: # %bb.0: -; X64-NEXT: movl %edi, %eax -; X64-NEXT: negl %eax -; X64-NEXT: andnl %edi, %eax, %eax +; X64-NEXT: blsrl %edi, %eax ; X64-NEXT: jne .LBB48_1 ; X64-NEXT: # %bb.2: ; X64-NEXT: jmp bar # TAILCALL @@ -1192,13 +1187,13 @@ define void @pr42118_i64(i64 %x) { ; X86-NEXT: .cfi_offset %esi, -8 ; X86-NEXT: movl {{[0-9]+}}(%esp), %eax ; X86-NEXT: movl {{[0-9]+}}(%esp), %ecx -; X86-NEXT: xorl %edx, %edx -; X86-NEXT: movl %eax, %esi -; X86-NEXT: negl %esi -; X86-NEXT: sbbl %ecx, %edx -; X86-NEXT: andnl %ecx, %edx, %ecx -; X86-NEXT: andnl %eax, %esi, %eax -; X86-NEXT: orl %ecx, %eax +; X86-NEXT: movl %eax, %edx +; X86-NEXT: addl $-1, %edx +; X86-NEXT: movl %ecx, %esi +; X86-NEXT: adcl $-1, %esi +; X86-NEXT: andl %eax, %edx +; X86-NEXT: andl %ecx, %esi +; X86-NEXT: orl %edx, %esi ; X86-NEXT: jne .LBB49_1 ; X86-NEXT: # %bb.2: ; X86-NEXT: popl %esi @@ -1212,9 +1207,7 @@ define void @pr42118_i64(i64 %x) { ; ; X64-LABEL: pr42118_i64: ; X64: # %bb.0: -; X64-NEXT: movq %rdi, %rax -; X64-NEXT: negq %rax -; X64-NEXT: andnq %rdi, %rax, %rax +; X64-NEXT: blsrq %rdi, %rax ; X64-NEXT: jne .LBB49_1 ; X64-NEXT: # %bb.2: ; X64-NEXT: jmp bar # TAILCALL |
