Add some more tests

Author: ckoparkar

llvm/test/CodeGen/AArch64/underflow-compare-fold.ll

@@ -2,6 +2,7 @@
 
 ; GitHub issue #161036
 
+; Positive test : umin(sub(a,b),a) with scalar types should be folded
 define i64 @underflow_compare_fold(i64 %a, i64 %b) {
 ; CHECK-LABEL: underflow_compare_fold
 ; CHECK:      // %bb.0:
@@ -12,3 +13,41 @@ define i64 @underflow_compare_fold(i64 %a, i64 %b) {
   %cond = tail call i64 @llvm.umin.i64(i64 %sub, i64 %a)
   ret i64 %cond
 }
+
+; Negative test, vector types : umin(sub(a,b),a) but with vectors
+define <16 x i8> @underflow_compare_dontfold_vectors(<16 x i8> %a, <16 x i8> %b) {
+; CHECK-LABEL: underflow_compare_dontfold_vectors
+; CHECK-LABEL: %bb.0
+; CHECK-NEXT: sub v1.16b, v0.16b, v1.16b
+; CHECK-NEXT: umin v0.16b, v1.16b, v0.16b
+; CHECK-NEXT: ret
+  %sub = sub <16 x i8> %a, %b
+  %cond = tail call <16 x i8> @llvm.umin.v16i8(<16 x i8> %sub, <16 x i8> %a)
+  ret <16 x i8> %cond
+}
+
+; Negative test, pattern mismatch : umin(a,sub(a,b))
+define i64 @umin_sub_inverse_args(i64 %a, i64 %b) {
+; CHECK-LABEL: umin_sub_inverse_args
+; CHECK-LABEL: %bb.0
+; CHECK-NEXT: sub x8, x0, x1
+; CHECK-NEXT: cmp x0, x8
+; CHECK-NEXT: csel x0, x0, x8, lo
+; CHECK-NEXT: ret
+  %sub = sub i64 %a, %b
+  %cond = tail call i64 @llvm.umin.i64(i64 %a, i64 %sub)
+  ret i64 %cond
+}
+
+; Negative test, pattern mismatch : umin(add(a,b),a)
+define i64 @umin_add(i64 %a, i64 %b) {
+; CHECK-LABEL: umin_add
+; CHECK-LABEL: %bb.0
+; CHECK-NEXT: add x8, x0, x1
+; CHECK-NEXT: cmp x8, x0
+; CHECK-NEXT: csel x0, x8, x0, lo
+; CHECK-NEXT: ret
+  %add = add i64 %a, %b
+  %cond = tail call i64 @llvm.umin.i64(i64 %add, i64 %a)
+  ret i64 %cond
+}

llvm/test/CodeGen/X86/underflow-compare-fold.ll

@@ -2,6 +2,7 @@
 
 ; GitHub issue #161036
 
+; Positive test : umin(sub(a,b),a) with scalar types should be folded
 define i64 @underflow_compare_fold(i64 %a, i64 %b) {
 ; CHECK-LABEL: underflow_compare_fold
 ; CHECK-LABEL: %bb.0
@@ -13,3 +14,43 @@ define i64 @underflow_compare_fold(i64 %a, i64 %b) {
   %cond = tail call i64 @llvm.umin.i64(i64 %sub, i64 %a)
   ret i64 %cond
 }
+
+; Negative test, vector types : umin(sub(a,b),a) but with vectors
+define <16 x i8> @underflow_compare_dontfold_vectors(<16 x i8> %a, <16 x i8> %b) {
+; CHECK-LABEL: underflow_compare_dontfold_vectors
+; CHECK-LABEL: %bb.0
+; CHECK-NEXT: movdqa %xmm0, %xmm2
+; CHECK-NEXT: psubb %xmm1, %xmm2
+; CHECK-NEXT: pminub %xmm2, %xmm0
+; CHECK-NEXT: retq
+  %sub = sub <16 x i8> %a, %b
+  %cond = tail call <16 x i8> @llvm.umin.v16i8(<16 x i8> %sub, <16 x i8> %a)
+  ret <16 x i8> %cond
+}
+
+; Negative test, pattern mismatch : umin(a,sub(a,b))
+define i64 @umin_sub_inverse_args(i64 %a, i64 %b) {
+; CHECK-LABEL: umin_sub_inverse_args
+; CHECK-LABEL: %bb.0
+; CHECK-NEXT: movq %rdi, %rax
+; CHECK-NEXT: subq %rsi, %rax
+; CHECK-NEXT: cmpq %rax, %rdi
+; CHECK-NEXT: cmovbq %rdi, %rax
+; CHECK-NEXT: retq
+  %sub = sub i64 %a, %b
+  %cond = tail call i64 @llvm.umin.i64(i64 %a, i64 %sub)
+  ret i64 %cond
+}
+
+; Negative test, pattern mismatch : umin(add(a,b),a)
+define i64 @umin_add(i64 %a, i64 %b) {
+; CHECK-LABEL: umin_add
+; CHECK-LABEL: %bb.0
+; CHECK-NEXT: leaq (%rsi,%rdi), %rax
+; CHECK-NEXT: cmpq %rdi, %rax
+; CHECK-NEXT: cmovaeq %rdi, %rax
+; CHECK-NEXT: retq
+  %add = add i64 %a, %b
+  %cond = tail call i64 @llvm.umin.i64(i64 %add, i64 %a)
+  ret i64 %cond
+}