[NVPTX] Use approximate FP ops when unsafe-fp-math is used, and append

.ftz to instructions if the nvptx-f32ftz attribute is set to "true"

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186820 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 43 insertions, 0 deletions

diff --git a/test/CodeGen/NVPTX/fast-math.ll b/test/CodeGen/NVPTX/fast-math.ll
new file mode 100644
index 0000000..9da26ad
--- /dev/null
+++ b/test/CodeGen/NVPTX/fast-math.ll
@@ -0,0 +1,43 @@
+; RUN: llc < %s -march=nvptx -mcpu=sm_20 | FileCheck %s
+
+
+declare float @llvm.nvvm.sqrt.f(float)
+
+
+; CHECK: sqrt_div
+; CHECK: sqrt.rn.f32
+; CHECK: div.rn.f32
+define float @sqrt_div(float %a, float %b) {
+  %t1 = tail call float @llvm.nvvm.sqrt.f(float %a)
+  %t2 = fdiv float %t1, %b
+  ret float %t2
+}
+
+; CHECK: sqrt_div_fast
+; CHECK: sqrt.approx.f32
+; CHECK: div.approx.f32
+define float @sqrt_div_fast(float %a, float %b) #0 {
+  %t1 = tail call float @llvm.nvvm.sqrt.f(float %a)
+  %t2 = fdiv float %t1, %b
+  ret float %t2
+}
+
+
+; CHECK: fadd
+; CHECK: add.f32
+define float @fadd(float %a, float %b) {
+  %t1 = fadd float %a, %b
+  ret float %t1
+}
+
+; CHECK: fadd_ftz
+; CHECK: add.ftz.f32
+define float @fadd_ftz(float %a, float %b) #1 {
+  %t1 = fadd float %a, %b
+  ret float %t1
+}
+
+
+
+attributes #0 = { "unsafe-fp-math" = "true" }
+attributes #1 = { "nvptx-f32ftz" = "true" }