llvm-project/llvm/test/CodeGen/X86/setcc-lowering.ll

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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -mtriple=x86_64-unknown-unknown -mattr=+avx < %s | FileCheck %s --check-prefix=AVX
; RUN: llc -mtriple=i386-unknown-linux-gnu -mcpu=knl < %s | FileCheck %s --check-prefix=KNL-32
[x86] Fix wrong lowering of vsetcc nodes (PR25080). Function LowerVSETCC (in X86ISelLowering.cpp) worked under the wrong assumption that for non-AVX512 targets, the source type and destination type of a type-legalized setcc node were always the same type. This assumption was unfortunately incorrect; the type legalizer is not always able to promote the return type of a setcc to the same type as the first operand of a setcc. In the case of a vsetcc node, the legalizer firstly checks if the first input operand has a legal type. If so, then it promotes the return type of the vsetcc to that same type. Otherwise, the return type is promoted to the 'next legal type', which, for vectors of MVT::i1 is always a 128-bit integer vector type. Example (-mattr=+avx): %0 = trunc <8 x i32> %a to <8 x i23> %1 = icmp eq <8 x i23> %0, zeroinitializer The initial selection dag for the code above is: v8i1 = setcc t5, t7, seteq:ch t5: v8i23 = truncate t2 t2: v8i32,ch = CopyFromReg t0, Register:v8i32 %vreg1 t7: v8i32 = build_vector of all zeroes. The type legalizer would firstly check if 't5' has a legal type. If so, then it would reuse that same type to promote the return type of the setcc node. Unfortunately 't5' is of illegal type v8i23, and therefore it cannot be used to promote the return type of the setcc node. Consequently, the setcc return type is promoted to v8i16. Later on, 't5' is promoted to v8i32 thus leading to the following dag node: v8i16 = setcc t32, t25, seteq:ch where t32 and t25 are now values of type v8i32. Before this patch, function LowerVSETCC would have wrongly expanded the setcc to a single X86ISD::PCMPEQ. Surprisingly, ISel was still able to match an instruction. In our case, ISel would have matched a VPCMPEQWrr: t37: v8i16 = X86ISD::VPCMPEQWrr t36, t25 However, t36 and t25 are both VR256, while the result type is instead of class VR128. This inconsistency ended up causing the insertion of COPY instructions like this: %vreg7<def> = COPY %vreg3; VR128:%vreg7 VR256:%vreg3 Which is an invalid full copy (not a sub register copy). Eventually, the backend would have hit an UNREACHABLE "Cannot emit physreg copy instruction" in the attempt to expand the malformed pseudo COPY instructions. This patch fixes the problem adding the missing logic in LowerVSETCC to handle the corner case of a setcc with 128-bit return type and 256-bit operand type. This problem was originally reported by Dimitry as PR25080. It has been latent for a very long time. I have added the minimal reproducible from that bugzilla as test setcc-lowering.ll. Differential Revision: http://reviews.llvm.org/D13660 llvm-svn: 250085
2015-10-13 03:22:30 +08:00
; Verify that we don't crash during codegen due to a wrong lowering
; of a setcc node with illegal operand types and return type.
define <8 x i16> @pr25080(<8 x i32> %a) {
; AVX-LABEL: pr25080:
; AVX: # BB#0: # %entry
; AVX-NEXT: vandps {{.*}}(%rip), %ymm0, %ymm0
; AVX-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX-NEXT: vpxor %xmm2, %xmm2, %xmm2
; AVX-NEXT: vpcmpeqd %xmm2, %xmm1, %xmm1
; AVX-NEXT: vpcmpeqd %xmm2, %xmm0, %xmm0
; AVX-NEXT: vpacksswb %xmm1, %xmm0, %xmm0
; AVX-NEXT: vpor {{.*}}(%rip), %xmm0, %xmm0
; AVX-NEXT: vpsllw $15, %xmm0, %xmm0
; AVX-NEXT: vpsraw $15, %xmm0, %xmm0
; AVX-NEXT: vzeroupper
; AVX-NEXT: retq
;
; KNL-32-LABEL: pr25080:
; KNL-32: # BB#0: # %entry
; KNL-32-NEXT: vpbroadcastd {{\.LCPI.*}}, %ymm1
; KNL-32-NEXT: vpand %ymm1, %ymm0, %ymm0
; KNL-32-NEXT: vpxor %ymm1, %ymm1, %ymm1
; KNL-32-NEXT: vpcmpeqd %zmm1, %zmm0, %k0
; KNL-32-NEXT: movb $15, %al
; KNL-32-NEXT: kmovw %eax, %k1
; KNL-32-NEXT: korw %k1, %k0, %k1
; KNL-32-NEXT: vpternlogq $255, %zmm0, %zmm0, %zmm0 {%k1} {z}
; KNL-32-NEXT: vpmovqw %zmm0, %xmm0
; KNL-32-NEXT: retl
[x86] Fix wrong lowering of vsetcc nodes (PR25080). Function LowerVSETCC (in X86ISelLowering.cpp) worked under the wrong assumption that for non-AVX512 targets, the source type and destination type of a type-legalized setcc node were always the same type. This assumption was unfortunately incorrect; the type legalizer is not always able to promote the return type of a setcc to the same type as the first operand of a setcc. In the case of a vsetcc node, the legalizer firstly checks if the first input operand has a legal type. If so, then it promotes the return type of the vsetcc to that same type. Otherwise, the return type is promoted to the 'next legal type', which, for vectors of MVT::i1 is always a 128-bit integer vector type. Example (-mattr=+avx): %0 = trunc <8 x i32> %a to <8 x i23> %1 = icmp eq <8 x i23> %0, zeroinitializer The initial selection dag for the code above is: v8i1 = setcc t5, t7, seteq:ch t5: v8i23 = truncate t2 t2: v8i32,ch = CopyFromReg t0, Register:v8i32 %vreg1 t7: v8i32 = build_vector of all zeroes. The type legalizer would firstly check if 't5' has a legal type. If so, then it would reuse that same type to promote the return type of the setcc node. Unfortunately 't5' is of illegal type v8i23, and therefore it cannot be used to promote the return type of the setcc node. Consequently, the setcc return type is promoted to v8i16. Later on, 't5' is promoted to v8i32 thus leading to the following dag node: v8i16 = setcc t32, t25, seteq:ch where t32 and t25 are now values of type v8i32. Before this patch, function LowerVSETCC would have wrongly expanded the setcc to a single X86ISD::PCMPEQ. Surprisingly, ISel was still able to match an instruction. In our case, ISel would have matched a VPCMPEQWrr: t37: v8i16 = X86ISD::VPCMPEQWrr t36, t25 However, t36 and t25 are both VR256, while the result type is instead of class VR128. This inconsistency ended up causing the insertion of COPY instructions like this: %vreg7<def> = COPY %vreg3; VR128:%vreg7 VR256:%vreg3 Which is an invalid full copy (not a sub register copy). Eventually, the backend would have hit an UNREACHABLE "Cannot emit physreg copy instruction" in the attempt to expand the malformed pseudo COPY instructions. This patch fixes the problem adding the missing logic in LowerVSETCC to handle the corner case of a setcc with 128-bit return type and 256-bit operand type. This problem was originally reported by Dimitry as PR25080. It has been latent for a very long time. I have added the minimal reproducible from that bugzilla as test setcc-lowering.ll. Differential Revision: http://reviews.llvm.org/D13660 llvm-svn: 250085
2015-10-13 03:22:30 +08:00
entry:
%0 = trunc <8 x i32> %a to <8 x i23>
%1 = icmp eq <8 x i23> %0, zeroinitializer
%2 = or <8 x i1> %1, <i1 true, i1 true, i1 true, i1 true, i1 false, i1 false, i1 false, i1 false>
%3 = sext <8 x i1> %2 to <8 x i16>
ret <8 x i16> %3
}
define void @pr26232(i64 %a, <16 x i1> %b) {
; AVX-LABEL: pr26232:
; AVX: # BB#0: # %for_loop599.preheader
; AVX-NEXT: vpxor %xmm1, %xmm1, %xmm1
; AVX-NEXT: vmovdqa {{.*#+}} xmm2 = [128,128,128,128,128,128,128,128,128,128,128,128,128,128,128,128]
; AVX-NEXT: .p2align 4, 0x90
; AVX-NEXT: .LBB1_1: # %for_loop599
; AVX-NEXT: # =>This Inner Loop Header: Depth=1
; AVX-NEXT: xorl %eax, %eax
; AVX-NEXT: cmpq $65536, %rdi # imm = 0x10000
; AVX-NEXT: setl %al
; AVX-NEXT: vmovd %eax, %xmm3
; AVX-NEXT: vpshufb %xmm1, %xmm3, %xmm3
; AVX-NEXT: vpand %xmm0, %xmm3, %xmm3
; AVX-NEXT: vpsllw $7, %xmm3, %xmm3
; AVX-NEXT: vpand %xmm2, %xmm3, %xmm3
; AVX-NEXT: vpcmpgtb %xmm3, %xmm1, %xmm3
; AVX-NEXT: vpmovmskb %xmm3, %eax
; AVX-NEXT: testw %ax, %ax
; AVX-NEXT: jne .LBB1_1
; AVX-NEXT: # BB#2: # %for_exit600
; AVX-NEXT: retq
;
; KNL-32-LABEL: pr26232:
2016-04-05 22:06:20 +08:00
; KNL-32: # BB#0: # %for_loop599.preheader
; KNL-32-NEXT: pushl %esi
; KNL-32-NEXT: .Lcfi0:
; KNL-32-NEXT: .cfi_def_cfa_offset 8
; KNL-32-NEXT: .Lcfi1:
; KNL-32-NEXT: .cfi_offset %esi, -8
; KNL-32-NEXT: vpmovsxbd %xmm0, %zmm0
; KNL-32-NEXT: vpslld $31, %zmm0, %zmm0
; KNL-32-NEXT: vptestmd %zmm0, %zmm0, %k0
; KNL-32-NEXT: movl {{[0-9]+}}(%esp), %eax
; KNL-32-NEXT: movl {{[0-9]+}}(%esp), %ecx
; KNL-32-NEXT: movw $-1, %dx
; KNL-32-NEXT: .p2align 4, 0x90
; KNL-32-NEXT: .LBB1_1: # %for_loop599
; KNL-32-NEXT: # =>This Inner Loop Header: Depth=1
; KNL-32-NEXT: cmpl $65536, %ecx # imm = 0x10000
; KNL-32-NEXT: movl %eax, %esi
; KNL-32-NEXT: sbbl $0, %esi
; KNL-32-NEXT: movl $0, %esi
; KNL-32-NEXT: cmovlw %dx, %si
; KNL-32-NEXT: kmovw %esi, %k1
; KNL-32-NEXT: kandw %k0, %k1, %k1
; KNL-32-NEXT: kmovw %k1, %esi
; KNL-32-NEXT: testw %si, %si
; KNL-32-NEXT: jne .LBB1_1
; KNL-32-NEXT: # BB#2: # %for_exit600
; KNL-32-NEXT: popl %esi
[X86] Correct dwarf unwind information in function epilogue CFI instructions that set appropriate cfa offset and cfa register are now inserted in emitEpilogue() in X86FrameLowering. Majority of the changes in this patch: 1. Ensure that CFI instructions do not affect code generation. 2. Enable maintaining correct information about cfa offset and cfa register in a function when basic blocks are reordered, merged, split, duplicated. These changes are target independent and described below. Changed CFI instructions so that they: 1. are duplicable 2. are not counted as instructions when tail duplicating or tail merging 3. can be compared as equal Add information to each MachineBasicBlock about cfa offset and cfa register that are valid at its entry and exit (incoming and outgoing CFI info). Add support for updating this information when basic blocks are merged, split, duplicated, created. Add a verification pass (CFIInfoVerifier) that checks that outgoing cfa offset and register of predecessor blocks match incoming values of their successors. Incoming and outgoing CFI information is used by a late pass (CFIInstrInserter) that corrects CFA calculation rule for a basic block if needed. That means that additional CFI instructions get inserted at basic block beginning to correct the rule for calculating CFA. Having CFI instructions in function epilogue can cause incorrect CFA calculation rule for some basic blocks. This can happen if, due to basic block reordering, or the existence of multiple epilogue blocks, some of the blocks have wrong cfa offset and register values set by the epilogue block above them. Patch by Violeta Vukobrat. Differential Revision: https://reviews.llvm.org/D18046 llvm-svn: 306529
2017-06-28 18:21:17 +08:00
; KNL-32-NEXT: .Lcfi2:
; KNL-32-NEXT: .cfi_def_cfa_offset 4
; KNL-32-NEXT: retl
allocas:
br label %for_test11.preheader
for_test11.preheader: ; preds = %for_test11.preheader, %allocas
br i1 undef, label %for_loop599, label %for_test11.preheader
for_loop599: ; preds = %for_loop599, %for_test11.preheader
%less_i_load605_ = icmp slt i64 %a, 65536
%less_i_load605__broadcast_init = insertelement <16 x i1> undef, i1 %less_i_load605_, i32 0
%less_i_load605__broadcast = shufflevector <16 x i1> %less_i_load605__broadcast_init, <16 x i1> undef, <16 x i32> zeroinitializer
%"oldMask&test607" = and <16 x i1> %less_i_load605__broadcast, %b
%intmask.i894 = bitcast <16 x i1> %"oldMask&test607" to i16
%res.i895 = icmp eq i16 %intmask.i894, 0
br i1 %res.i895, label %for_exit600, label %for_loop599
for_exit600: ; preds = %for_loop599
ret void
}