InlineSpiller: Delete assert that implicit_def has no implicit operands

[arsenm]

It's not a verifier enforced property that implicit_def may only have one operand. Fixes assertions after the coalescer implicit-defs to preserve super register liveness to arbitrary instructions.

For some reason I'm unable to reproduce this as a MIR test running only the allocator for the x86 test. Not sure it's worth keeping around.

[llvmbot]

@llvm/pr-subscribers-llvm-regalloc
@llvm/pr-subscribers-backend-aarch64

@llvm/pr-subscribers-backend-x86

Author: Matt Arsenault (arsenm)

Changes

It's not a verifier enforced property that implicit_def may only have one operand. Fixes assertions after the coalescer implicit-defs to preserve super register liveness to arbitrary instructions.

For some reason I'm unable to reproduce this as a MIR test running only the allocator for the x86 test. Not sure it's worth keeping around.

---

Full diff: https://github.com/llvm/llvm-project/pull/69087.diff

3 Files Affected:

• (modified) llvm/lib/CodeGen/InlineSpiller.cpp (+1-2)
• (added) llvm/test/CodeGen/AArch64/implicit-def-with-impdef-greedy-assert.mir (+181)
• (added) llvm/test/CodeGen/X86/inline-spiller-impdef-on-implicit-def-regression.ll (+181)

diff --git a/llvm/lib/CodeGen/InlineSpiller.cpp b/llvm/lib/CodeGen/InlineSpiller.cpp
index c62f3db9d321562..46fcc62e09e8a8c 100644
--- a/llvm/lib/CodeGen/InlineSpiller.cpp
+++ b/llvm/lib/CodeGen/InlineSpiller.cpp
@@ -1071,8 +1071,7 @@ void InlineSpiller::insertReload(Register NewVReg,
 static bool isRealSpill(const MachineInstr &Def) {
   if (!Def.isImplicitDef())
     return true;
-  assert(Def.getNumOperands() == 1 &&
-         "Implicit def with more than one definition");
+
   // We can say that the VReg defined by Def is undef, only if it is
   // fully defined by Def. Otherwise, some of the lanes may not be
   // undef and the value of the VReg matters.
diff --git a/llvm/test/CodeGen/AArch64/implicit-def-with-impdef-greedy-assert.mir b/llvm/test/CodeGen/AArch64/implicit-def-with-impdef-greedy-assert.mir
new file mode 100644
index 000000000000000..c79c951fdc15247
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/implicit-def-with-impdef-greedy-assert.mir
@@ -0,0 +1,181 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 3
+# RUN: llc -mtriple=arm64-apple-ios -run-pass=greedy -o - %s | FileCheck %s
+
+---
+name:            widget
+tracksRegLiveness: true
+jumpTable:
+  kind:            label-difference32
+  entries:
+    - id:              0
+      blocks:          [ '%bb.9', '%bb.5', '%bb.2', '%bb.2', '%bb.2' ]
+body:             |
+  ; CHECK-LABEL: name: widget
+  ; CHECK: bb.0:
+  ; CHECK-NEXT:   successors: %bb.1(0x80000000)
+  ; CHECK-NEXT:   liveins: $w0, $w1, $x2, $x3, $x4, $w5, $w6
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   [[DEF:%[0-9]+]]:gpr64common = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF1:%[0-9]+]]:gpr64 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF2:%[0-9]+]]:gpr32common = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF3:%[0-9]+]]:gpr32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF4:%[0-9]+]]:gpr32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF5:%[0-9]+]]:gpr64common = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF6:%[0-9]+]]:gpr32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   undef [[DEF7:%[0-9]+]].sub_32:gpr64 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF8:%[0-9]+]]:gpr64common = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF9:%[0-9]+]]:gpr32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   dead [[DEF10:%[0-9]+]]:gpr64 = IMPLICIT_DEF
+  ; CHECK-NEXT:   undef [[DEF11:%[0-9]+]].sub_32:gpr64 = IMPLICIT_DEF implicit-def dead %11
+  ; CHECK-NEXT:   STRXui [[DEF11]], %stack.0, 0 :: (store (s64) into %stack.0)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.1:
+  ; CHECK-NEXT:   successors: %bb.2(0x80000000)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.2:
+  ; CHECK-NEXT:   successors: %bb.3(0x0fbefbf0), %bb.4(0x70410410)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   Bcc 8, %bb.3, implicit killed undef $nzcv
+  ; CHECK-NEXT:   B %bb.4
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.3:
+  ; CHECK-NEXT:   successors: %bb.11(0x00000000), %bb.2(0x80000000)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   dead $wzr = SUBSWri [[DEF2]], 64, 0, implicit-def $nzcv
+  ; CHECK-NEXT:   Bcc 0, %bb.11, implicit killed undef $nzcv
+  ; CHECK-NEXT:   B %bb.2
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.4:
+  ; CHECK-NEXT:   successors: %bb.9(0x01288b01), %bb.5(0x01288b01), %bb.2(0x11f46a91), %bb.6(0x23e8d524), %bb.7(0x47d1aa49)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   dead early-clobber %12:gpr64, dead early-clobber %13:gpr64sp = JumpTableDest32 [[DEF8]], [[DEF7]], %jump-table.0
+  ; CHECK-NEXT:   BR undef %18:gpr64
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.5:
+  ; CHECK-NEXT:   successors: %bb.8(0x80000000)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   B %bb.8
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.6:
+  ; CHECK-NEXT:   successors: %bb.2(0x80000000)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   STRWui [[DEF9]], [[DEF5]], 0 :: (store (s32))
+  ; CHECK-NEXT:   B %bb.2
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.7:
+  ; CHECK-NEXT:   successors: %bb.2(0x80000000)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   STRWui $wzr, [[DEF]], 0 :: (store (s32))
+  ; CHECK-NEXT:   ADJCALLSTACKDOWN 0, 0, implicit-def dead $sp, implicit $sp
+  ; CHECK-NEXT:   $w0 = COPY [[DEF4]]
+  ; CHECK-NEXT:   $x1 = COPY [[DEF1]]
+  ; CHECK-NEXT:   BL 0, csr_darwin_aarch64_aapcs, implicit-def dead $lr, implicit $sp, implicit-def $sp, implicit-def dead $w0
+  ; CHECK-NEXT:   ADJCALLSTACKUP 0, 0, implicit-def dead $sp, implicit $sp
+  ; CHECK-NEXT:   ADJCALLSTACKDOWN 0, 0, implicit-def dead $sp, implicit $sp
+  ; CHECK-NEXT:   $w0 = COPY [[DEF6]]
+  ; CHECK-NEXT:   ADJCALLSTACKUP 0, 0, implicit-def dead $sp, implicit $sp
+  ; CHECK-NEXT:   B %bb.2
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.8:
+  ; CHECK-NEXT:   successors: %bb.8(0x80000000)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   B %bb.8
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.9:
+  ; CHECK-NEXT:   successors: %bb.10(0x40000000), %bb.1(0x40000000)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   undef [[DEF12:%[0-9]+]].sub_32:gpr64 = IMPLICIT_DEF
+  ; CHECK-NEXT:   STRXui [[DEF12]], %stack.0, 0 :: (store (s64) into %stack.0)
+  ; CHECK-NEXT:   TBZW [[DEF3]], 0, %bb.1
+  ; CHECK-NEXT:   B %bb.10
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.10:
+  ; CHECK-NEXT:   successors: %bb.1(0x80000000)
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   ADJCALLSTACKDOWN 32, 0, implicit-def dead $sp, implicit $sp
+  ; CHECK-NEXT:   ADJCALLSTACKUP 32, 0, implicit-def dead $sp, implicit $sp
+  ; CHECK-NEXT:   B %bb.1
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT: bb.11:
+  ; CHECK-NEXT:   [[LDRXui:%[0-9]+]]:gpr64 = LDRXui %stack.0, 0 :: (load (s64) from %stack.0)
+  ; CHECK-NEXT:   dead undef [[COPY:%[0-9]+]].sub_32:gpr64 = COPY [[LDRXui]].sub_32
+  ; CHECK-NEXT:   ADJCALLSTACKDOWN 8, 0, implicit-def dead $sp, implicit $sp
+  ; CHECK-NEXT:   ADJCALLSTACKUP 8, 0, implicit-def dead $sp, implicit $sp
+  bb.0:
+    liveins: $w0, $w1, $x2, $x3, $x4, $w5, $w6
+
+    %0:gpr64common = IMPLICIT_DEF
+    %1:gpr64 = IMPLICIT_DEF
+    %2:gpr32common = IMPLICIT_DEF
+    %3:gpr32 = IMPLICIT_DEF
+    %4:gpr32 = IMPLICIT_DEF
+    %5:gpr64common = IMPLICIT_DEF
+    %6:gpr32 = IMPLICIT_DEF
+    undef %7.sub_32:gpr64 = IMPLICIT_DEF
+    %8:gpr64common = IMPLICIT_DEF
+    %9:gpr32 = IMPLICIT_DEF
+    %10:gpr64 = IMPLICIT_DEF
+    undef %10.sub_32:gpr64 = IMPLICIT_DEF implicit-def %11:gpr64
+
+  bb.1:
+
+  bb.2:
+    successors: %bb.3(0x0fbefbf0), %bb.4(0x70410410)
+
+    Bcc 8, %bb.3, implicit killed undef $nzcv
+    B %bb.4
+
+  bb.3:
+    successors: %bb.11(0x00000000), %bb.2(0x80000000)
+
+    dead $wzr = SUBSWri %2, 64, 0, implicit-def $nzcv
+    Bcc 0, %bb.11, implicit killed undef $nzcv
+    B %bb.2
+
+  bb.4:
+    successors: %bb.9(0x01288b01), %bb.5(0x01288b01), %bb.2(0x11f46a91), %bb.6(0x23e8d524), %bb.7(0x47d1aa49)
+
+    early-clobber %12:gpr64, dead early-clobber %13:gpr64sp = JumpTableDest32 %8, %7, %jump-table.0
+    BR undef %10
+
+  bb.5:
+    B %bb.8
+
+  bb.6:
+    STRWui %9, %5, 0 :: (store (s32))
+    B %bb.2
+
+  bb.7:
+    STRWui $wzr, %0, 0 :: (store (s32))
+    ADJCALLSTACKDOWN 0, 0, implicit-def dead $sp, implicit $sp
+    $w0 = COPY %4
+    $x1 = COPY %1
+    BL 0, csr_darwin_aarch64_aapcs, implicit-def dead $lr, implicit $sp, implicit-def $sp, implicit-def dead $w0
+    ADJCALLSTACKUP 0, 0, implicit-def dead $sp, implicit $sp
+    ADJCALLSTACKDOWN 0, 0, implicit-def dead $sp, implicit $sp
+    $w0 = COPY %6
+    ADJCALLSTACKUP 0, 0, implicit-def dead $sp, implicit $sp
+    B %bb.2
+
+  bb.8:
+    B %bb.8
+
+  bb.9:
+    successors: %bb.10, %bb.1
+
+    undef %10.sub_32:gpr64 = IMPLICIT_DEF
+    TBZW %3, 0, %bb.1
+    B %bb.10
+
+  bb.10:
+    ADJCALLSTACKDOWN 32, 0, implicit-def dead $sp, implicit $sp
+    ADJCALLSTACKUP 32, 0, implicit-def dead $sp, implicit $sp
+    B %bb.1
+
+  bb.11:
+    undef %14.sub_32:gpr64 = COPY %10.sub_32
+    ADJCALLSTACKDOWN 8, 0, implicit-def dead $sp, implicit $sp
+    ADJCALLSTACKUP 8, 0, implicit-def dead $sp, implicit $sp
+
+...
diff --git a/llvm/test/CodeGen/X86/inline-spiller-impdef-on-implicit-def-regression.ll b/llvm/test/CodeGen/X86/inline-spiller-impdef-on-implicit-def-regression.ll
new file mode 100644
index 000000000000000..1449f9a700965a0
--- /dev/null
+++ b/llvm/test/CodeGen/X86/inline-spiller-impdef-on-implicit-def-regression.ll
@@ -0,0 +1,181 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 3
+; RUN: llc -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s
+
+; Make sure there's no assert on an implicit-def with implicit operands
+; during register allocation.
+
+%struct.BlockContext = type { [32 x i8], [32 x i8], [2 x [32 x i8]], [32 x i8], [32 x i8], [32 x i8], [32 x i8], [32 x i8], [2 x [32 x i8]], [2 x [32 x i8]], [32 x i8], [32 x i8], [32 x i8], [32 x i8], [16 x i8], [32 x i8], [32 x i8] }
+%struct.CdfModeContext = type { [4 x [16 x i16]], [2 x [13 x [16 x i16]]], [9 x [16 x i16]], [5 x [4 x [16 x i16]]], [6 x [16 x i16]], [2 x [16 x i16]], [16 x i16], [2 x [13 x [8 x i16]]], [3 x [13 x [8 x i16]]], [8 x i16], [8 x [8 x i16]], [8 x i16], [8 x [8 x i16]], [3 x [8 x i16]], [2 x [7 x [8 x i16]]], [2 x [7 x [5 x [8 x i16]]]], [2 x [8 x [4 x i16]]], [4 x [3 x [4 x i16]]], [22 x [4 x i16]], [4 x i16], [5 x [4 x i16]], [4 x [4 x i16]], [4 x i16], [2 x i16], [2 x i16], [7 x [2 x i16]], [7 x [2 x i16]], [4 x [2 x i16]], [22 x [2 x i16]], [6 x [2 x i16]], [2 x [2 x i16]], [6 x [2 x i16]], [3 x [2 x i16]], [4 x [2 x i16]], [5 x [2 x i16]], [5 x [2 x i16]], [6 x [2 x i16]], [6 x [2 x i16]], [9 x [2 x i16]], [6 x [3 x [2 x i16]]], [3 x [3 x [2 x i16]]], [2 x [3 x [2 x i16]]], [3 x [3 x [2 x i16]]], [7 x [3 x [2 x i16]]], [3 x [2 x i16]], [3 x [2 x i16]], [3 x [2 x i16]], [22 x [2 x i16]], [7 x [3 x [2 x i16]]], [2 x [2 x i16]], [2 x i16], [8 x i8] }
+
+define i32 @decode_sb(ptr %t, i32 %bl, i32 %_msprop1966, i32 %sub.i, i64 %idxprom, i1 %cmp54) #0 {
+; CHECK-LABEL: decode_sb:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    pushq %rbp
+; CHECK-NEXT:    .cfi_def_cfa_offset 16
+; CHECK-NEXT:    .cfi_offset %rbp, -16
+; CHECK-NEXT:    movq %rsp, %rbp
+; CHECK-NEXT:    .cfi_def_cfa_register %rbp
+; CHECK-NEXT:    pushq %r15
+; CHECK-NEXT:    pushq %r14
+; CHECK-NEXT:    pushq %r13
+; CHECK-NEXT:    pushq %r12
+; CHECK-NEXT:    pushq %rbx
+; CHECK-NEXT:    subq $24, %rsp
+; CHECK-NEXT:    .cfi_offset %rbx, -56
+; CHECK-NEXT:    .cfi_offset %r12, -48
+; CHECK-NEXT:    .cfi_offset %r13, -40
+; CHECK-NEXT:    .cfi_offset %r14, -32
+; CHECK-NEXT:    .cfi_offset %r15, -24
+; CHECK-NEXT:    movl %r9d, %ebx
+; CHECK-NEXT:    movabsq $87960930222080, %r15 # imm = 0x500000000000
+; CHECK-NEXT:    movl 0, %r13d
+; CHECK-NEXT:    movl %esi, %r12d
+; CHECK-NEXT:    # implicit-def: $eax
+; CHECK-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; CHECK-NEXT:    testb $1, %bl
+; CHECK-NEXT:    jne .LBB0_9
+; CHECK-NEXT:  # %bb.1: # %if.else
+; CHECK-NEXT:    movq %r8, %r14
+; CHECK-NEXT:    movl %ecx, %eax
+; CHECK-NEXT:    andl $1, %eax
+; CHECK-NEXT:    movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; CHECK-NEXT:    movzbl 544(%rax), %eax
+; CHECK-NEXT:    andl $1, %eax
+; CHECK-NEXT:    movl %r15d, %r9d
+; CHECK-NEXT:    andl $1, %r9d
+; CHECK-NEXT:    movl %r14d, %r10d
+; CHECK-NEXT:    andl $1, %r10d
+; CHECK-NEXT:    movl %esi, %r11d
+; CHECK-NEXT:    # kill: def $cl killed $cl killed $ecx
+; CHECK-NEXT:    shrl %cl, %r11d
+; CHECK-NEXT:    movabsq $17592186044416, %r8 # imm = 0x100000000000
+; CHECK-NEXT:    orq %r10, %r8
+; CHECK-NEXT:    andl $2, %r11d
+; CHECK-NEXT:    testb $1, %bl
+; CHECK-NEXT:    cmoveq %r9, %r8
+; CHECK-NEXT:    movl %edx, %ecx
+; CHECK-NEXT:    orq %rax, %rcx
+; CHECK-NEXT:    movq %r13, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill
+; CHECK-NEXT:    orq $1, %r13
+; CHECK-NEXT:    orl %esi, %r11d
+; CHECK-NEXT:    movl $1, %edx
+; CHECK-NEXT:    je .LBB0_3
+; CHECK-NEXT:  # %bb.2: # %if.else
+; CHECK-NEXT:    movl (%r8), %edx
+; CHECK-NEXT:  .LBB0_3: # %if.else
+; CHECK-NEXT:    shlq $5, %rcx
+; CHECK-NEXT:    movq %r12, %rsi
+; CHECK-NEXT:    shlq $7, %rsi
+; CHECK-NEXT:    addq %rcx, %rsi
+; CHECK-NEXT:    addq $1248, %rsi # imm = 0x4E0
+; CHECK-NEXT:    movq %r13, 0
+; CHECK-NEXT:    movq %rdi, %r15
+; CHECK-NEXT:    movl %edx, (%rdi)
+; CHECK-NEXT:    xorl %eax, %eax
+; CHECK-NEXT:    xorl %edi, %edi
+; CHECK-NEXT:    xorl %edx, %edx
+; CHECK-NEXT:    callq *%rax
+; CHECK-NEXT:    xorq $1, %r14
+; CHECK-NEXT:    cmpl $0, (%r14)
+; CHECK-NEXT:    je .LBB0_6
+; CHECK-NEXT:  # %bb.4: # %if.else
+; CHECK-NEXT:    movb $1, %al
+; CHECK-NEXT:    testb %al, %al
+; CHECK-NEXT:    je .LBB0_5
+; CHECK-NEXT:  .LBB0_6: # %bb19
+; CHECK-NEXT:    testb $1, %bl
+; CHECK-NEXT:    movq %r15, %rdi
+; CHECK-NEXT:    movabsq $87960930222080, %r15 # imm = 0x500000000000
+; CHECK-NEXT:    movq {{[-0-9]+}}(%r{{[sb]}}p), %r13 # 8-byte Reload
+; CHECK-NEXT:    je .LBB0_9
+; CHECK-NEXT:  # %bb.7: # %land.lhs.true56
+; CHECK-NEXT:    xorl %eax, %eax
+; CHECK-NEXT:    jmp .LBB0_8
+; CHECK-NEXT:  .LBB0_9: # %if.end69
+; CHECK-NEXT:    movl %r13d, 0
+; CHECK-NEXT:    xorl %eax, %eax
+; CHECK-NEXT:    xorl %esi, %esi
+; CHECK-NEXT:    xorl %edx, %edx
+; CHECK-NEXT:    xorl %ecx, %ecx
+; CHECK-NEXT:    xorl %r8d, %r8d
+; CHECK-NEXT:    callq *%rax
+; CHECK-NEXT:    xorq %r15, %r12
+; CHECK-NEXT:    movslq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 4-byte Folded Reload
+; CHECK-NEXT:    movzbl (%r12), %ecx
+; CHECK-NEXT:    movb %cl, 544(%rax)
+; CHECK-NEXT:    xorl %eax, %eax
+; CHECK-NEXT:  .LBB0_8: # %land.lhs.true56
+; CHECK-NEXT:    addq $24, %rsp
+; CHECK-NEXT:    popq %rbx
+; CHECK-NEXT:    popq %r12
+; CHECK-NEXT:    popq %r13
+; CHECK-NEXT:    popq %r14
+; CHECK-NEXT:    popq %r15
+; CHECK-NEXT:    popq %rbp
+; CHECK-NEXT:    .cfi_def_cfa %rsp, 8
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB0_5: # %bb
+entry:
+  %i = load i32, ptr null, align 8
+  br i1 %cmp54, label %if.end69, label %if.else
+
+if.else:                                          ; preds = %entry
+  %shr18 = and i32 %sub.i, 1
+  %idxprom.i = zext i32 %shr18 to i64
+  %arrayidx.i = getelementptr %struct.BlockContext, ptr null, i64 0, i32 14, i64 %idxprom.i
+  %i1 = load i8, ptr %arrayidx.i, align 1
+  %conv.i = zext i8 %i1 to i32
+  %and.i = and i32 %conv.i, 1
+  %i2 = and i64 87960930222080, 1
+  %i3 = inttoptr i64 %i2 to ptr
+  %i4 = load i32, ptr %i3, align 4
+  %i5 = and i64 %idxprom, 1
+  %i6 = or i64 %i5, 17592186044416
+  %i7 = inttoptr i64 %i6 to ptr
+  %i8 = load i32, ptr %i7, align 4
+  %i9 = lshr i32 %bl, %sub.i
+  %i10 = and i32 %i9, 2
+  %i11 = or i32 %bl, %i10
+  %i12 = select i1 %cmp54, i32 %i8, i32 %i4
+  %add.i = or i32 %_msprop1966, %and.i
+  %idxprom4 = zext i32 %bl to i64
+  %idxprom24 = zext i32 %add.i to i64
+  %i13 = or i32 %i, 1
+  %i14 = zext i32 %i13 to i64
+  %.not2329 = icmp eq i32 %i11, 0
+  %i15 = select i1 %.not2329, i32 1, i32 %i12
+  %arrayidx25 = getelementptr %struct.CdfModeContext, ptr null, i64 0, i32 3, i64 %idxprom4, i64 %idxprom24
+  store i64 %i14, ptr null, align 8
+  store i32 %i15, ptr %t, align 4
+  %call53 = tail call i32 null(ptr null, ptr %arrayidx25, i64 0)
+  %i16 = xor i64 %idxprom, 1
+  %i17 = inttoptr i64 %i16 to ptr
+  %_msld1992 = load i32, ptr %i17, align 8
+  %i18 = icmp ne i32 %_msld1992, 0
+  %_msprop_icmp1993 = and i1 %i18, false
+  br i1 %_msprop_icmp1993, label %bb, label %bb19
+
+bb:                                               ; preds = %if.else
+  unreachable
+
+bb19:                                             ; preds = %if.else
+  br i1 %cmp54, label %land.lhs.true56, label %if.end69
+
+land.lhs.true56:                                  ; preds = %bb19
+  ret i32 0
+
+if.end69:                                         ; preds = %bb19, %entry
+  %bx8.011941201 = phi i32 [ %shr18, %bb19 ], [ undef, %entry ]
+  store i32 %i, ptr null, align 8
+  %call79 = tail call fastcc i32 null(ptr %t, i32 0, i32 0, i32 0, i32 0)
+  %idxprom666 = zext i32 %bl to i64
+  %i20 = xor i64 %idxprom666, 87960930222080
+  %idxprom675 = sext i32 %bx8.011941201 to i64
+  %arrayidx676 = getelementptr %struct.BlockContext, ptr null, i64 0, i32 14, i64 %idxprom675
+  %i21 = inttoptr i64 %i20 to ptr
+  %_msld1414 = load i8, ptr %i21, align 1
+  store i8 %_msld1414, ptr %arrayidx676, align 1
+  ret i32 0
+}
+
+attributes #0 = { "frame-pointer"="all" "target-cpu"="x86-64" }

[qcolombet]

If we really want to keep an assert here, we could check that we have only one explicit operand.
Don't think that's worth it though.

[arsenm]

The verifier handles that case