[SystemZ] Add LOC and LOCG
As with the stores, these instructions can trap when the condition is false,
so they are only used for things like (cond ? x : *ptr).
llvm-svn: 187112
diff --git a/llvm/test/CodeGen/SystemZ/cond-load-01.ll b/llvm/test/CodeGen/SystemZ/cond-load-01.ll
new file mode 100644
index 0000000..59ed90c
--- /dev/null
+++ b/llvm/test/CodeGen/SystemZ/cond-load-01.ll
@@ -0,0 +1,130 @@
+; Test LOC.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=z196 | FileCheck %s
+
+declare i32 @foo(i32 *)
+
+; Test the simple case.
+define i32 @f1(i32 %easy, i32 *%ptr, i32 %limit) {
+; CHECK-LABEL: f1:
+; CHECK: clfi %r4, 42
+; CHECK: locnl %r2, 0(%r3)
+; CHECK: br %r14
+ %cond = icmp ult i32 %limit, 42
+ %other = load i32 *%ptr
+ %res = select i1 %cond, i32 %easy, i32 %other
+ ret i32 %res
+}
+
+; ...and again with the operands swapped.
+define i32 @f2(i32 %easy, i32 *%ptr, i32 %limit) {
+; CHECK-LABEL: f2:
+; CHECK: clfi %r4, 42
+; CHECK: locl %r2, 0(%r3)
+; CHECK: br %r14
+ %cond = icmp ult i32 %limit, 42
+ %other = load i32 *%ptr
+ %res = select i1 %cond, i32 %other, i32 %easy
+ ret i32 %res
+}
+
+; Check the high end of the aligned LOC range.
+define i32 @f3(i32 %easy, i32 *%base, i32 %limit) {
+; CHECK-LABEL: f3:
+; CHECK: clfi %r4, 42
+; CHECK: locnl %r2, 524284(%r3)
+; CHECK: br %r14
+ %ptr = getelementptr i32 *%base, i64 131071
+ %cond = icmp ult i32 %limit, 42
+ %other = load i32 *%ptr
+ %res = select i1 %cond, i32 %easy, i32 %other
+ ret i32 %res
+}
+
+; Check the next word up. Other sequences besides this one would be OK.
+define i32 @f4(i32 %easy, i32 *%base, i32 %limit) {
+; CHECK-LABEL: f4:
+; CHECK: agfi %r3, 524288
+; CHECK: clfi %r4, 42
+; CHECK: locnl %r2, 0(%r3)
+; CHECK: br %r14
+ %ptr = getelementptr i32 *%base, i64 131072
+ %cond = icmp ult i32 %limit, 42
+ %other = load i32 *%ptr
+ %res = select i1 %cond, i32 %easy, i32 %other
+ ret i32 %res
+}
+
+; Check the low end of the LOC range.
+define i32 @f5(i32 %easy, i32 *%base, i32 %limit) {
+; CHECK-LABEL: f5:
+; CHECK: clfi %r4, 42
+; CHECK: locnl %r2, -524288(%r3)
+; CHECK: br %r14
+ %ptr = getelementptr i32 *%base, i64 -131072
+ %cond = icmp ult i32 %limit, 42
+ %other = load i32 *%ptr
+ %res = select i1 %cond, i32 %easy, i32 %other
+ ret i32 %res
+}
+
+; Check the next word down, with the same comments as f4.
+define i32 @f6(i32 %easy, i32 *%base, i32 %limit) {
+; CHECK-LABEL: f6:
+; CHECK: agfi %r3, -524292
+; CHECK: clfi %r4, 42
+; CHECK: locnl %r2, 0(%r3)
+; CHECK: br %r14
+ %ptr = getelementptr i32 *%base, i64 -131073
+ %cond = icmp ult i32 %limit, 42
+ %other = load i32 *%ptr
+ %res = select i1 %cond, i32 %easy, i32 %other
+ ret i32 %res
+}
+
+; Try a frame index base.
+define i32 @f7(i32 %alt, i32 %limit) {
+; CHECK-LABEL: f7:
+; CHECK: brasl %r14, foo@PLT
+; CHECK: locnl %r2, {{[0-9]+}}(%r15)
+; CHECK: br %r14
+ %ptr = alloca i32
+ %easy = call i32 @foo(i32 *%ptr)
+ %cond = icmp ult i32 %limit, 42
+ %other = load i32 *%ptr
+ %res = select i1 %cond, i32 %easy, i32 %other
+ ret i32 %res
+}
+
+; Try a case when an index is involved.
+define i32 @f8(i32 %easy, i32 %limit, i64 %base, i64 %index) {
+; CHECK-LABEL: f8:
+; CHECK: clfi %r3, 42
+; CHECK: locnl %r2, 0({{%r[1-5]}})
+; CHECK: br %r14
+ %add = add i64 %base, %index
+ %ptr = inttoptr i64 %add to i32 *
+ %cond = icmp ult i32 %limit, 42
+ %other = load i32 *%ptr
+ %res = select i1 %cond, i32 %easy, i32 %other
+ ret i32 %res
+}
+
+; Test that conditionally-executed loads do not use LOC, since it is allowed
+; to trap even when the condition is false.
+define i32 @f9(i32 %easy, i32 %limit, i32 *%ptr) {
+; CHECK-LABEL: f9:
+; CHECK-NOT: loc
+; CHECK: br %r14
+entry:
+ %cmp = icmp ule i32 %easy, %limit
+ br i1 %cmp, label %load, label %exit
+
+load:
+ %other = load i32 *%ptr
+ br label %exit
+
+exit:
+ %res = phi i32 [ %easy, %entry ], [ %other, %load ]
+ ret i32 %res
+}