Subzero: Local variable splitting.

tests_lit/llvm2ice_tests/multidef_kill.ll

 ; This tests against a lowering error in a multiply instruction that produces
 ; results in a low and high register.  This is usually lowered as a mul
 ; instruction whose dest contains the low portion, and a FakeDef of the high
 ; portion.  The problem is that if the high portion is unused (e.g. the multiply
 ; is followed by a truncation), the FakeDef may be eliminated, and the register
 ; allocator may assign the high register to a variable that is live across the
 ; mul instruction.  This is incorrect because the mul instruction smashes the
 ; register.
 
 ; REQUIRES: allow_dump
 
 ; RUN: %p2i --target x8632 -i %s --filetype=asm --args -O2 -asm-verbose \
+; RUN:   --split-local-vars=0 \
 ; RUN:   --reg-use=eax,edx -reg-reserve | FileCheck --check-prefix=X8632 %s
 ; RUN: %p2i --target arm32 -i %s --filetype=asm --args -O2 -asm-verbose \
 ; RUN:   | FileCheck --check-prefix=ARM32 %s
 
 define internal i32 @mul(i64 %a, i64 %b, i32 %c) {
   ; Force an early use of %c.
   store i32 %c, i32* undef, align 1
   %m = mul i64 %a, %b
   %t = trunc i64 %m to i32
   ; Make many uses of %c to give it high weight.
   %t1 = add i32 %t, %c
   %t2 = add i32 %t1, %c
   %t3 = add i32 %t2, %c
   ret i32 %t3
 }
 
 ; For x8632, we want asm-verbose to print the stack offset assignment for lv$c
 ; ("local variable 'c'") in the prolog, and then have at least one use of lv$c
 ; in the body, i.e. don't register-allocate edx to %c.
 
 ; X8632-LABEL: mul
 ; X8632: lv$c =
 ; X8632: lv$c
 
 ; For arm32, the failure would manifest as a translation error - no register
 ; being allocated to the high operand, so we just check for successful
 ; translation.
 
 ; ARM32-LABEL: mul