Reland "[X86][APX] Remove redundant TEST*ri instructions" (#156002)

phoebewang · web-flow · commit 59082485e6c5 · 2025-08-29T14:51:40.000Z
The goal is to remove redundant TEST*ri instructions, especially with NF feature. Other tests are side effects due to longer live range of EFLAGS. https://godbolt.org/z/PbaTj1oa3 Reland with fix to buildbot failures.
diff --git a/llvm/lib/Target/X86/X86InstrInfo.cpp b/llvm/lib/Target/X86/X86InstrInfo.cpp
@@ -4898,6 +4898,16 @@ bool X86InstrInfo::analyzeCompare(const MachineInstr &MI, Register &SrcReg,
     CmpMask = ~0;
     CmpValue = 0;
     return true;
+  case X86::TEST64ri32:
+  case X86::TEST32ri:
+  case X86::TEST16ri:
+  case X86::TEST8ri:
+    SrcReg = MI.getOperand(0).getReg();
+    SrcReg2 = 0;
+    // Force identical compare.
+    CmpMask = 0;
+    CmpValue = 0;
+    return true;
   }
   return false;
 }
@@ -4937,6 +4947,10 @@ bool X86InstrInfo::isRedundantFlagInstr(const MachineInstr &FlagI,
   case X86::CMP32ri:
   case X86::CMP16ri:
   case X86::CMP8ri:
+  case X86::TEST64ri32:
+  case X86::TEST32ri:
+  case X86::TEST16ri:
+  case X86::TEST8ri:
   CASE_ND(SUB64ri32)
   CASE_ND(SUB32ri)
   CASE_ND(SUB16ri)
diff --git a/llvm/test/CodeGen/X86/2007-11-30-LoadFolding-Bug.ll b/llvm/test/CodeGen/X86/2007-11-30-LoadFolding-Bug.ll
@@ -13,25 +13,24 @@ define fastcc void @mp_sqrt(i32 %n, i32 %radix, ptr %in, ptr %out, ptr %tmp1, pt
 ; CHECK-NEXT:    pushl %edi
 ; CHECK-NEXT:    pushl %esi
 ; CHECK-NEXT:    pushl %eax
-; CHECK-NEXT:    movb $1, %cl
+; CHECK-NEXT:    movb $1, %al
 ; CHECK-NEXT:    movl $1, %ebx
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %esi
 ; CHECK-NEXT:    .p2align 4
 ; CHECK-NEXT:  .LBB0_1: # %bb.i5
 ; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
-; CHECK-NEXT:    movl %ecx, %eax
+; CHECK-NEXT:    movl %eax, %ecx
 ; CHECK-NEXT:    addl %ebx, %ebx
-; CHECK-NEXT:    xorl %ecx, %ecx
-; CHECK-NEXT:    testb $1, %al
+; CHECK-NEXT:    xorl %eax, %eax
+; CHECK-NEXT:    testb $1, %cl
 ; CHECK-NEXT:    jne .LBB0_1
 ; CHECK-NEXT:  # %bb.2: # %mp_unexp_mp2d.exit.i
 ; CHECK-NEXT:    je .LBB0_3
 ; CHECK-NEXT:  # %bb.5: # %cond_next.i
-; CHECK-NEXT:    testb $1, %al
 ; CHECK-NEXT:    jne .LBB0_3
 ; CHECK-NEXT:  # %bb.6: # %cond_next36.i
 ; CHECK-NEXT:    movl $0, 0
-; CHECK-NEXT:    movzbl %al, %ebp
+; CHECK-NEXT:    movzbl %cl, %ebp
 ; CHECK-NEXT:    andl $1, %ebp
 ; CHECK-NEXT:    xorpd %xmm0, %xmm0
 ; CHECK-NEXT:    xorl %eax, %eax
diff --git a/llvm/test/CodeGen/X86/2008-04-17-CoalescerBug.ll b/llvm/test/CodeGen/X86/2008-04-17-CoalescerBug.ll
@@ -38,7 +38,6 @@ define void @_ZNK10wxDateTime6FormatEPKwRKNS_8TimeZoneE(ptr noalias sret(%struct
 ; CHECK-NEXT:  ## %bb.1: ## %bb116.i
 ; CHECK-NEXT:    je LBB0_25
 ; CHECK-NEXT:  ## %bb.2: ## %bb52.i.i
-; CHECK-NEXT:    testb $1, %bl
 ; CHECK-NEXT:    je LBB0_25
 ; CHECK-NEXT:  ## %bb.3: ## %bb142.i
 ; CHECK-NEXT:    je LBB0_25
@@ -49,23 +48,23 @@ define void @_ZNK10wxDateTime6FormatEPKwRKNS_8TimeZoneE(ptr noalias sret(%struct
 ; CHECK-NEXT:    jmp LBB0_5
 ; CHECK-NEXT:  LBB0_21: ## %bb7806
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
-; CHECK-NEXT:  Ltmp16:
+; CHECK-NEXT:  Ltmp16: ## EH_LABEL
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $1, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, (%esp)
 ; CHECK-NEXT:    calll __ZN12wxStringBase6appendEmw
-; CHECK-NEXT:  Ltmp17:
+; CHECK-NEXT:  Ltmp17: ## EH_LABEL
 ; CHECK-NEXT:  LBB0_5: ## %bb3261
 ; CHECK-NEXT:    ## =>This Inner Loop Header: Depth=1
 ; CHECK-NEXT:    cmpl $37, 0
 ; CHECK-NEXT:    jne LBB0_25
 ; CHECK-NEXT:  ## %bb.6: ## %bb3306
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
-; CHECK-NEXT:  Ltmp0:
+; CHECK-NEXT:  Ltmp0: ## EH_LABEL
 ; CHECK-NEXT:    movl %edi, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, (%esp)
 ; CHECK-NEXT:    calll __ZN12wxStringBaseaSEPKw
-; CHECK-NEXT:  Ltmp1:
+; CHECK-NEXT:  Ltmp1: ## EH_LABEL
 ; CHECK-NEXT:  ## %bb.7: ## %bb3314
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
 ; CHECK-NEXT:    movl 0, %eax
@@ -89,11 +88,11 @@ define void @_ZNK10wxDateTime6FormatEPKwRKNS_8TimeZoneE(ptr noalias sret(%struct
 ; CHECK-NEXT:    je LBB0_14
 ; CHECK-NEXT:  ## %bb.13: ## %bb155.i8541
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
-; CHECK-NEXT:  Ltmp4:
+; CHECK-NEXT:  Ltmp4: ## EH_LABEL
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, (%esp)
 ; CHECK-NEXT:    calll _gmtime_r
-; CHECK-NEXT:  Ltmp5:
+; CHECK-NEXT:  Ltmp5: ## EH_LABEL
 ; CHECK-NEXT:  LBB0_14: ## %bb182.i8560
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
 ; CHECK-NEXT:    testb $1, %bl
@@ -103,7 +102,7 @@ define void @_ZNK10wxDateTime6FormatEPKwRKNS_8TimeZoneE(ptr noalias sret(%struct
 ; CHECK-NEXT:    je LBB0_18
 ; CHECK-NEXT:  ## %bb.17: ## %bb440.i8663
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
-; CHECK-NEXT:  Ltmp6:
+; CHECK-NEXT:  Ltmp6: ## EH_LABEL
 ; CHECK-NEXT:    movl L_.str4$non_lazy_ptr, %eax
 ; CHECK-NEXT:    movl %eax, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl L_.str33$non_lazy_ptr, %eax
@@ -113,47 +112,47 @@ define void @_ZNK10wxDateTime6FormatEPKwRKNS_8TimeZoneE(ptr noalias sret(%struct
 ; CHECK-NEXT:    movl %ebp, (%esp)
 ; CHECK-NEXT:    movl $1717, {{[0-9]+}}(%esp) ## imm = 0x6B5
 ; CHECK-NEXT:    calll __Z10wxOnAssertPKwiPKcS0_S0_
-; CHECK-NEXT:  Ltmp7:
+; CHECK-NEXT:  Ltmp7: ## EH_LABEL
 ; CHECK-NEXT:    jmp LBB0_18
 ; CHECK-NEXT:  LBB0_15: ## %bb187.i8591
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
 ; CHECK-NEXT:    jne LBB0_25
 ; CHECK-NEXT:  LBB0_18: ## %invcont5814
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
-; CHECK-NEXT:  Ltmp8:
+; CHECK-NEXT:  Ltmp8: ## EH_LABEL
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, (%esp)
 ; CHECK-NEXT:    calll __ZN8wxString6FormatEPKwz
 ; CHECK-NEXT:    subl $4, %esp
-; CHECK-NEXT:  Ltmp9:
+; CHECK-NEXT:  Ltmp9: ## EH_LABEL
 ; CHECK-NEXT:  ## %bb.19: ## %invcont5831
 ; CHECK-NEXT:    ## in Loop: Header=BB0_5 Depth=1
-; CHECK-NEXT:  Ltmp10:
+; CHECK-NEXT:  Ltmp10: ## EH_LABEL
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, (%esp)
 ; CHECK-NEXT:    calll __ZN12wxStringBase10ConcatSelfEmPKwm
-; CHECK-NEXT:  Ltmp11:
+; CHECK-NEXT:  Ltmp11: ## EH_LABEL
 ; CHECK-NEXT:    jmp LBB0_5
 ; CHECK-NEXT:  LBB0_9: ## %bb5657
-; CHECK-NEXT:  Ltmp13:
+; CHECK-NEXT:  Ltmp13: ## EH_LABEL
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    movl %eax, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    movl %eax, (%esp)
 ; CHECK-NEXT:    calll __ZNK10wxDateTime12GetDayOfYearERKNS_8TimeZoneE
-; CHECK-NEXT:  Ltmp14:
+; CHECK-NEXT:  Ltmp14: ## EH_LABEL
 ; CHECK-NEXT:    jmp LBB0_25
 ; CHECK-NEXT:  LBB0_20: ## %bb5968
-; CHECK-NEXT:  Ltmp2:
+; CHECK-NEXT:  Ltmp2: ## EH_LABEL
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl $0, (%esp)
 ; CHECK-NEXT:    calll __ZN8wxString6FormatEPKwz
 ; CHECK-NEXT:    subl $4, %esp
-; CHECK-NEXT:  Ltmp3:
+; CHECK-NEXT:  Ltmp3: ## EH_LABEL
 ; CHECK-NEXT:  LBB0_25: ## %bb115.critedge.i
 ; CHECK-NEXT:    movl %esi, %eax
 ; CHECK-NEXT:    addl $28, %esp
@@ -163,13 +162,13 @@ define void @_ZNK10wxDateTime6FormatEPKwRKNS_8TimeZoneE(ptr noalias sret(%struct
 ; CHECK-NEXT:    popl %ebp
 ; CHECK-NEXT:    retl $4
 ; CHECK-NEXT:  LBB0_23: ## %lpad.loopexit.split-lp
-; CHECK-NEXT:  Ltmp15:
+; CHECK-NEXT:  Ltmp15: ## EH_LABEL
 ; CHECK-NEXT:    jmp LBB0_25
 ; CHECK-NEXT:  LBB0_24: ## %lpad8185
-; CHECK-NEXT:  Ltmp12:
+; CHECK-NEXT:  Ltmp12: ## EH_LABEL
 ; CHECK-NEXT:    jmp LBB0_25
 ; CHECK-NEXT:  LBB0_22: ## %lpad.loopexit
-; CHECK-NEXT:  Ltmp18:
+; CHECK-NEXT:  Ltmp18: ## EH_LABEL
 ; CHECK-NEXT:    jmp LBB0_25
 ; CHECK-NEXT:  Lfunc_end0:
 entry:
diff --git a/llvm/test/CodeGen/X86/apx/cf.ll b/llvm/test/CodeGen/X86/apx/cf.ll
@@ -229,3 +229,21 @@ entry:
   call void @llvm.masked.store.v1i32.p0(<1 x i32> zeroinitializer, ptr %p, i32 1, <1 x i1> %1)
   ret void
 }
+
+define i64 @redundant_test(i64 %num, ptr %p1, i64 %in) {
+; CHECK-LABEL: redundant_test:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    testl $-32, %edi
+; CHECK-NEXT:    cfcmoveq (%rsi), %rax
+; CHECK-NEXT:    {nf} addq %rdx, %rax
+; CHECK-NEXT:    cmovneq %rdi, %rax
+; CHECK-NEXT:    retq
+  %and = and i64 %num, 4294967264
+  %cmp = icmp eq i64 %and, 0
+  %mask = bitcast i1 %cmp to <1 x i1>
+  %condload = tail call <1 x i64> @llvm.masked.load.v1i64.p0(ptr %p1, i32 8, <1 x i1> %mask, <1 x i64> poison)
+  %v = bitcast <1 x i64> %condload to i64
+  %add = add i64 %v, %in
+  %sel = select i1 %cmp, i64 %add, i64 %num
+  ret i64 %sel
+}
diff --git a/llvm/test/CodeGen/X86/ins_subreg_coalesce-3.ll b/llvm/test/CodeGen/X86/ins_subreg_coalesce-3.ll
@@ -22,41 +22,45 @@ define void @FontChange(i1 %foo) nounwind {
 ; CHECK-LABEL: FontChange:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    testb $1, %dil
-; CHECK-NEXT:    je .LBB0_10
+; CHECK-NEXT:    je .LBB0_12
+; CHECK-NEXT:  # %bb.1: # %bb298
+; CHECK-NEXT:    je .LBB0_3
+; CHECK-NEXT:  # %bb.2: # %bb304
+; CHECK-NEXT:    je .LBB0_4
 ; CHECK-NEXT:    .p2align 4
-; CHECK-NEXT:  .LBB0_1: # %bb366
+; CHECK-NEXT:  .LBB0_3: # %bb366
 ; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
 ; CHECK-NEXT:    testb $1, %dil
-; CHECK-NEXT:    jne .LBB0_1
-; CHECK-NEXT:  # %bb.2: # %bb428
+; CHECK-NEXT:    jne .LBB0_3
+; CHECK-NEXT:  .LBB0_4: # %bb428
 ; CHECK-NEXT:    testb $1, %dil
-; CHECK-NEXT:    je .LBB0_10
-; CHECK-NEXT:  # %bb.3:
+; CHECK-NEXT:    je .LBB0_12
+; CHECK-NEXT:  # %bb.5:
 ; CHECK-NEXT:    cmpb $0, 0
 ; CHECK-NEXT:    .p2align 4
-; CHECK-NEXT:  .LBB0_4: # %bb650
+; CHECK-NEXT:  .LBB0_6: # %bb650
 ; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
-; CHECK-NEXT:    je .LBB0_4
-; CHECK-NEXT:  # %bb.5: # %bb662
+; CHECK-NEXT:    je .LBB0_6
+; CHECK-NEXT:  # %bb.7: # %bb662
 ; CHECK-NEXT:    movl 0, %eax
 ; CHECK-NEXT:    movl %eax, %ecx
 ; CHECK-NEXT:    andl $57344, %ecx # imm = 0xE000
 ; CHECK-NEXT:    cmpl $8192, %ecx # imm = 0x2000
-; CHECK-NEXT:    jne .LBB0_10
-; CHECK-NEXT:  # %bb.6: # %bb4884
+; CHECK-NEXT:    jne .LBB0_12
+; CHECK-NEXT:  # %bb.8: # %bb4884
 ; CHECK-NEXT:    andl $7168, %eax # imm = 0x1C00
 ; CHECK-NEXT:    cmpl $1024, %eax # imm = 0x400
-; CHECK-NEXT:    jne .LBB0_10
-; CHECK-NEXT:  # %bb.7: # %bb4932
+; CHECK-NEXT:    jne .LBB0_12
+; CHECK-NEXT:  # %bb.9: # %bb4932
 ; CHECK-NEXT:    testb $1, %dil
-; CHECK-NEXT:    jne .LBB0_10
-; CHECK-NEXT:  # %bb.8: # %bb4940
+; CHECK-NEXT:    jne .LBB0_12
+; CHECK-NEXT:  # %bb.10: # %bb4940
 ; CHECK-NEXT:    movl 0, %eax
 ; CHECK-NEXT:    cmpl $160, %eax
-; CHECK-NEXT:    je .LBB0_10
-; CHECK-NEXT:  # %bb.9: # %bb4940
+; CHECK-NEXT:    je .LBB0_12
+; CHECK-NEXT:  # %bb.11: # %bb4940
 ; CHECK-NEXT:    cmpl $159, %eax
-; CHECK-NEXT:  .LBB0_10: # %bb4897
+; CHECK-NEXT:  .LBB0_12: # %bb4897
 ; CHECK-NEXT:    retq
 entry:
 	br i1 %foo, label %bb298, label %bb49
diff --git a/llvm/test/CodeGen/X86/peep-test-5.ll b/llvm/test/CodeGen/X86/peep-test-5.ll
@@ -51,3 +51,54 @@ end:
 }
 
 declare void @free_object()
+
+; Check TEST instruction would not be combined with CMP.
+define i1 @pr155586(i8 %0) {
+; CHECK-LABEL: pr155586:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    cmpb $1, %dil
+; CHECK-NEXT:    setne %cl
+; CHECK-NEXT:    testb $1, %dil
+; CHECK-NEXT:    sete %al
+; CHECK-NEXT:    andb %cl, %al
+; CHECK-NEXT:    retq
+entry:
+  %cmp88.not = icmp eq i8 %0, 1
+  %1 = and i8 %0, 1
+  %tobool161.not = icmp eq i8 %1, 0
+  %common.ret.op = select i1 %cmp88.not, i1 false, i1 %tobool161.not
+  ret i1 %common.ret.op
+}
+
+; Check TEST8rr instruction would not be combined with TEST8ri.
+define i32 @pr155828() {
+; CHECK-LABEL: pr155828:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    xorl %eax, %eax
+; CHECK-NEXT:    .p2align 4
+; CHECK-NEXT:  .LBB2_1: # %func_188.exit.i.i
+; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
+; CHECK-NEXT:    movl %eax, %ecx
+; CHECK-NEXT:    movl $1, %eax
+; CHECK-NEXT:    testb $1, %cl
+; CHECK-NEXT:    jne .LBB2_1
+; CHECK-NEXT:  # %bb.2: # %if.else.i.i.i
+; CHECK-NEXT:    xorl %eax, %eax
+; CHECK-NEXT:    testb %cl, %cl
+; CHECK-NEXT:    setg %al
+; CHECK-NEXT:    retq
+entry:
+  br label %func_188.exit.i.i
+
+func_188.exit.i.i:                                ; preds = %func_188.exit.i.i, %entry
+  %or659.i167180.i.i = phi i32 [ 0, %entry ], [ 1, %func_188.exit.i.i ]
+  %conv48.i.i = trunc i32 %or659.i167180.i.i to i8
+  %and.i.i.i = and i32 %or659.i167180.i.i, 1
+  %tobool80.not.i.i.i = icmp eq i32 %and.i.i.i, 0
+  br i1 %tobool80.not.i.i.i, label %if.else.i.i.i, label %func_188.exit.i.i
+
+if.else.i.i.i:                                    ; preds = %func_188.exit.i.i
+  %cmp183.i.i.i = icmp sgt i8 %conv48.i.i, 0
+  %ext = zext i1 %cmp183.i.i.i to i32
+  ret i32 %ext
+}
diff --git a/llvm/test/CodeGen/X86/pr38795.ll b/llvm/test/CodeGen/X86/pr38795.ll
@@ -260,7 +260,6 @@ define void @verifier_error_reduced_issue38788(i1 %cmp11) {
 ; CHECK-NEXT:    pushl %ebx
 ; CHECK-NEXT:    .cfi_def_cfa_offset 8
 ; CHECK-NEXT:    .cfi_offset %ebx, -8
-; CHECK-NEXT:    movzbl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:    xorl %ecx, %ecx
 ; CHECK-NEXT:    xorl %ebx, %ebx
 ; CHECK-NEXT:    jmp .LBB1_1
@@ -272,23 +271,21 @@ define void @verifier_error_reduced_issue38788(i1 %cmp11) {
 ; CHECK-NEXT:    # in Loop: Header=BB1_1 Depth=1
 ; CHECK-NEXT:    movl %eax, %ecx
 ; CHECK-NEXT:    movl %edx, %ebx
-; CHECK-NEXT:    movzbl {{[0-9]+}}(%esp), %eax
 ; CHECK-NEXT:  .LBB1_1: # %for.cond
 ; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
-; CHECK-NEXT:    testb $1, %al
+; CHECK-NEXT:    testb $1, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    je .LBB1_3
 ; CHECK-NEXT:  # %bb.2: # in Loop: Header=BB1_1 Depth=1
 ; CHECK-NEXT:    xorl %eax, %eax
 ; CHECK-NEXT:    jmp .LBB1_5
 ; CHECK-NEXT:    .p2align 4
 ; CHECK-NEXT:  .LBB1_3: # %if.end
 ; CHECK-NEXT:    # in Loop: Header=BB1_1 Depth=1
-; CHECK-NEXT:    testb $1, %al
 ; CHECK-NEXT:    je .LBB1_4
 ; CHECK-NEXT:  # %bb.9: # %if.then13
 ; CHECK-NEXT:    # in Loop: Header=BB1_1 Depth=1
 ; CHECK-NEXT:    xorl %edx, %edx
-; CHECK-NEXT:    testb $1, %al
+; CHECK-NEXT:    testb $1, {{[0-9]+}}(%esp)
 ; CHECK-NEXT:    movl %ebx, %eax
 ; CHECK-NEXT:    movl $0, %ebx
 ; CHECK-NEXT:    jne .LBB1_8
