diff options
| author | Owen Anderson <resistor@mac.com> | 2010-10-05 17:24:05 +0000 |
|---|---|---|
| committer | Owen Anderson <resistor@mac.com> | 2010-10-05 17:24:05 +0000 |
| commit | 3a9e7690ba99c27d9b09fa8e61fb9f7ba01364c9 (patch) | |
| tree | e14a27741e7226959c730e67b77d7fb299788322 /test | |
| parent | 64227940e77216528452ff4c52365520349fb58d (diff) | |
Use a more efficient lowering of uint64_t --> float that can take advantage of hardware signed integer conversion without
having to do a double cast (uint64_t --> double --> float). This is based on the algorithm from compiler_rt's __floatundisf
for X86-64.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115634 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test')
| -rw-r--r-- | test/CodeGen/X86/uint64-to-float.ll | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/test/CodeGen/X86/uint64-to-float.ll b/test/CodeGen/X86/uint64-to-float.ll new file mode 100644 index 00000000000..d9f753c7a88 --- /dev/null +++ b/test/CodeGen/X86/uint64-to-float.ll @@ -0,0 +1,21 @@ +; RUN: llc < %s -march=x86-64 | FileCheck %s +; Verify that we are using the efficient uitofp --> sitofp lowering illustrated +; by the compiler_rt implementation of __floatundisf. +; <rdar://problem/8493982> + +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" +target triple = "x86_64-apple-darwin10.0.0" + +; CHECK: testq %rdi, %rdi +; CHECK-NEXT: jns LBB0_2 +; CHECK: shrq +; CHECK-NEXT: andq +; CHECK-NEXT: orq +; CHECK-NEXT: cvtsi2ss +; CHECK: LBB0_2 +; CHECK-NEXT: cvtsi2ss +define float @test(i64 %a) { +entry: + %b = uitofp i64 %a to float + ret float %b +} |