Add Om1 lowering with no optimizations

tests_lit/llvm2ice_tests/mangle.ll

+; Tests the Subzero "name mangling" when using the "llvm2ice --prefix"
+; option.
+
+; RUN: %llvm2ice --verbose none %s | FileCheck %s
+; RUN: %llvm2ice --verbose none --prefix Subzero %s | FileCheck --check-prefix=MANGLE %s
+; RUN: %llvm2ice --verbose none %s | FileCheck --check-prefix=ERRORS %s
+; RUN: %szdiff --llvm2ice=%llvm2ice %s | FileCheck --check-prefix=DUMP %s
+
+define internal void @FuncC(i32 %i) {
+entry:
+  ret void
+}
+; FuncC is a C symbol that isn't recognized as a C++ mangled symbol.
+; CHECK: FuncC:
+; MANGLE: SubzeroFuncC
+
+define internal void @_ZN13TestNamespace4FuncEi(i32 %i) {
+entry:
+  ret void
+}
+; This is Func(int) nested inside namespace TestNamespace.
+; CHECK: _ZN13TestNamespace4FuncEi:
+; MANGLE: _ZN7Subzero13TestNamespace4FuncEi:
+
+define internal void @_ZN13TestNamespace15NestedNamespace4FuncEi(i32 %i) {
+entry:
+  ret void
+}
+; This is Func(int) nested inside two namespaces.
+; CHECK: _ZN13TestNamespace15NestedNamespace4FuncEi:
+; MANGLE: _ZN7Subzero13TestNamespace15NestedNamespace4FuncEi:
+
+define internal void @_Z13FuncCPlusPlusi(i32 %i) {
+entry:
+  ret void
+}
+; This is a non-nested, mangled C++ symbol.
+; CHECK: _Z13FuncCPlusPlusi:
+; MANGLE: _ZN7Subzero13FuncCPlusPlusEi:
+
+define internal void @_ZN12_GLOBAL__N_18FuncAnonEi(i32 %i) {
+entry:
+  ret void
+}
+; This is FuncAnon(int) nested inside an anonymous namespace.
+; CHECK: _ZN12_GLOBAL__N_18FuncAnonEi:
+; MANGLE: _ZN7Subzero12_GLOBAL__N_18FuncAnonEi:
+
+; Now for the illegitimate examples.
+
+; Test for _ZN with no suffix.  Don't crash, prepend Subzero.
+define internal void @_ZN(i32 %i) {
+entry:
+  ret void
+}
+; MANGLE: Subzero_ZN:
+
+; Test for _Z<len><str> where <len> is smaller than it should be.
+define internal void @_Z12FuncCPlusPlusi(i32 %i) {
+entry:
+  ret void
+}
+; MANGLE: _ZN7Subzero12FuncCPlusPluEsi:
+
+; Test for _Z<len><str> where <len> is slightly larger than it should be.
+define internal void @_Z14FuncCPlusPlusi(i32 %i) {
+entry:
+  ret void
+}
+; MANGLE: _ZN7Subzero14FuncCPlusPlusiE:
+
+; Test for _Z<len><str> where <len> is much larger than it should be.
+define internal void @_Z114FuncCPlusPlusi(i32 %i) {
+entry:
+  ret void
+}
+; MANGLE: Subzero_Z114FuncCPlusPlusi:
+
+; Test for _Z<len><str> where we try to overflow the uint32_t holding <len>.
+define internal void @_Z4294967296FuncCPlusPlusi(i32 %i) {
+entry:
+  ret void
+}
+; MANGLE: Subzero_Z4294967296FuncCPlusPlusi:
+
+; Test for _Z<len><str> where <len> is 0.
+define internal void @_Z0FuncCPlusPlusi(i32 %i) {
+entry:
+  ret void
+}
+; MANGLE: _ZN7Subzero0EFuncCPlusPlusi:
+
+; Test for _Z<len><str> where <len> is -1.  LLVM explicitly allows the
+; '-' character in identifiers.
+
+define internal void @_Z-1FuncCPlusPlusi(i32 %i) {
+entry:
+  ret void
+}
+; MANGLE: Subzero_Z-1FuncCPlusPlusi:
+
+; ERRORS-NOT: ICE translation error
+; DUMP-NOT: SZ