[CodeGen] Round [SU]INT_TO_FP result when promoting from f16.

If we don't, values that aren't precisely representable in f16 could
be used as-is in a promoted f32 operation, which would produce
incorrect results.

AArch64 had the correct behavior; add a focused test.

Fixes http://llvm.org/PR26871

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268700 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 40 insertions, 0 deletions

diff --git a/test/CodeGen/ARM/fp16-promote.ll b/test/CodeGen/ARM/fp16-promote.ll
index 2a2eb8d2b6b..4da56b7ef35 100644
--- a/test/CodeGen/ARM/fp16-promote.ll
+++ b/test/CodeGen/ARM/fp16-promote.ll
@@ -889,4 +889,44 @@ define half @test_struct_arg(%struct.dummy %p) {
   ret half %a
 }
 
+; CHECK-LABEL: test_uitofp_i32_fadd:
+; CHECK-VFP-DAG: vcvt.f32.u32
+; CHECK-NOVFP-DAG: bl __aeabi_ui2f
+
+; CHECK-FP16-DAG: vcvtb.f16.f32
+; CHECK-FP16-DAG: vcvtb.f32.f16
+; CHECK-LIBCALL-DAG: bl __aeabi_h2f
+; CHECK-LIBCALL-DAG: bl __aeabi_h2f
+
+; CHECK-VFP-DAG: vadd.f32
+; CHECK-NOVFP-DAG: bl __aeabi_fadd
+
+; CHECK-FP16-DAG: vcvtb.f16.f32
+; CHECK-LIBCALL-DAG: bl __aeabi_f2h
+define half @test_uitofp_i32_fadd(i32 %a, half %b) #0 {
+  %c = uitofp i32 %a to half
+  %r = fadd half %b, %c
+  ret half %r
+}
+
+; CHECK-LABEL: test_sitofp_i32_fadd:
+; CHECK-VFP-DAG: vcvt.f32.s32
+; CHECK-NOVFP-DAG: bl __aeabi_i2f
+
+; CHECK-FP16-DAG: vcvtb.f16.f32
+; CHECK-FP16-DAG: vcvtb.f32.f16
+; CHECK-LIBCALL-DAG: bl __aeabi_h2f
+; CHECK-LIBCALL-DAG: bl __aeabi_h2f
+
+; CHECK-VFP-DAG: vadd.f32
+; CHECK-NOVFP-DAG: bl __aeabi_fadd
+
+; CHECK-FP16-DAG: vcvtb.f16.f32
+; CHECK-LIBCALL-DAG: bl __aeabi_f2h
+define half @test_sitofp_i32_fadd(i32 %a, half %b) #0 {
+  %c = sitofp i32 %a to half
+  %r = fadd half %b, %c
+  ret half %r
+}
+
 attributes #0 = { nounwind }