Subzero: Delete szdiff.py tests and ERRORS tests.

tests_lit/assembler/x86/opcode_register_encodings.ll

 ; Tests various aspects of x86 opcode encodings. E.g., some opcodes like
 ; those for pmull vary more wildly depending on operand size (rather than
 ; follow a usual pattern).
 
 ; RUN: %p2i -i %s --args -O2 -mattr=sse4.1 -sandbox --verbose none \
 ; RUN:   | llvm-mc -triple=i686-none-nacl -filetype=obj \
 ; RUN:   | llvm-objdump -d --symbolize -x86-asm-syntax=intel - | FileCheck %s
-; RUN: %p2i -i %s --args --verbose none | FileCheck --check-prefix=ERRORS %s
 
 define <8 x i16> @test_mul_v8i16(<8 x i16> %arg0, <8 x i16> %arg1) {
 entry:
   %res = mul <8 x i16> %arg0, %arg1
   ret <8 x i16> %res
 ; CHECK-LABEL: test_mul_v8i16
 ; CHECK: 66 0f d5 c1 pmullw xmm0, xmm1
 }
 
 ; Test register and address mode encoding.
@@ skipping 267 matching lines @@
 three:
   %res3 = extractelement <8 x i16> %vec4, i32 7
   %res3_ext = zext i16 %res3 to i32
   ret i32 %res3_ext
 }
 ; CHECK-LABEL: test_pextrw
 ; CHECK-DAG: 66 0f c5 c0 00 pextrw eax, xmm0, 0
 ; CHECK-DAG: 66 0f c5 c1 02 pextrw eax, xmm1, 2
 ; CHECK-DAG: 66 0f c5 c2 05 pextrw eax, xmm2, 5
 ; CHECK-DAG: 66 0f c5 c3 07 pextrw eax, xmm3, 7
-
-
-; ERRORS-NOT: ICE translation error