Start adding an integrated assembler.

tests_lit/assembler/x86/immediate_encodings.ll

+; Tests various aspects of x86 immediate encoding. Some encodings are shorter.
+; For example, the encoding is shorter for 8-bit immediates or when using EAX.
+; This assumes that EAX is chosen as the first free register in O2 mode.
+
+; RUN: %llvm2ice -O2 --verbose none %s \
+; RUN:   | llvm-mc -triple=i686-none-nacl -x86-asm-syntax=intel -filetype=obj \
+; RUN:   | llvm-objdump -d --symbolize -x86-asm-syntax=intel - | FileCheck %s
+; RUN: %llvm2ice --verbose none %s | FileCheck --check-prefix=ERRORS %s
+; RUN: %llvm2iceinsts %s | %szdiff %s | FileCheck --check-prefix=DUMP %s
+; RUN: %llvm2iceinsts --pnacl %s | %szdiff %s \
+; RUN:                           | FileCheck --check-prefix=DUMP %s
+
+define internal i32 @testXorImm8(i32 %arg) {
+entry:
+  %arg_i8 = trunc i32 %arg to i8
+  %result_i8 = xor i8 %arg_i8, 127
+  %result = zext i8 %result_i8 to i32
+  ret i32 %result
+}
+; CHECK-LABEL: testXorImm8
+; CHECK: 34 7f   xor al, 127
+
+define internal i32 @testXorImm8Neg(i32 %arg) {
+entry:
+  %arg_i8 = trunc i32 %arg to i8
+  %result_i8 = xor i8 %arg_i8, -56
+  %result = zext i8 %result_i8 to i32
+  ret i32 %result
+}
+; CHECK-LABEL: testXorImm8Neg
+; CHECK: 34 c8   xor al, -56
+
+define internal i32 @testXor32Imm8(i32 %arg) {
+entry:
+  %result = xor i32 %arg, 127
+  ret i32 %result
+}
+; CHECK-LABEL: testXor32Imm8
+; CHECK: 83 f0 7f   xor eax, 127
+
+define internal i32 @testXor32ImmEax(i32 %arg) {
+entry:
+  %result = xor i32 %arg, 32767
+  ret i32 %result
+}
+; CHECK-LABEL: testXor32ImmEax
+; CHECK: 35 ff 7f 00 00   xor eax, 32767
+
+define internal i32 @testXor32ImmGeneral(i32 %arg, i32 %arg2, i32 %arg3) {
+entry:
+  %x = xor i32 %arg, 32767
+  %x2 = xor i32 %arg2, 32767
+  %x3 = xor i32 %arg3, 32767
+  %add1 = add i32 %x, %x2
+  %add2 = add i32 %add1, %x3
+  ret i32 %add2
+}
+; CHECK-LABEL: testXor32ImmGeneral
+; CHECK: 81 f1 ff 7f 00 00   xor e{{[^a]}}x, 32767
+
+; ERRORS-NOT: ICE translation error
+; DUMP-NOT: SZ