From: I-Jui (Ray) Sung <ijsung@google.com>
Date: Fri, 9 Jun 2017 22:40:50 +0000 (+0000)
Subject: [AArch64] Add fallback in FastISel fp16 conversions
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9ac60a697c4b96f8cb98693719097e97127dc8bc;p=llvm

[AArch64] Add fallback in FastISel fp16 conversions

Summary:
- Fix assertion failures on F16 to/from int types in FastISel by falling
  back to regular ISel
- Add a testcase of various conversion cases with FastISel (-O0)

Reviewers: kristof.beyls, jmolloy, SjoerdMeijer

Reviewed By: SjoerdMeijer

Subscribers: SjoerdMeijer, llvm-commits, srhines, pirama, aemerson, rengolin, javed.absar, kristof.beyls

Differential Revision: https://reviews.llvm.org/D33734

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305127 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/AArch64/AArch64FastISel.cpp b/lib/Target/AArch64/AArch64FastISel.cpp
index 9ac7ecb9cdb..e8fcf1a0e9b 100644
--- a/lib/Target/AArch64/AArch64FastISel.cpp
+++ b/lib/Target/AArch64/AArch64FastISel.cpp
@@ -2827,7 +2827,7 @@ bool AArch64FastISel::selectFPToInt(const Instruction *I, bool Signed) {
     return false;
 
   EVT SrcVT = TLI.getValueType(DL, I->getOperand(0)->getType(), true);
-  if (SrcVT == MVT::f128)
+  if (SrcVT == MVT::f128 || SrcVT == MVT::f16)
     return false;
 
   unsigned Opc;
@@ -2854,6 +2854,10 @@ bool AArch64FastISel::selectIntToFP(const Instruction *I, bool Signed) {
   MVT DestVT;
   if (!isTypeLegal(I->getType(), DestVT) || DestVT.isVector())
     return false;
+  // Let regular ISEL handle FP16
+  if (DestVT == MVT::f16)
+    return false;
+
   assert((DestVT == MVT::f32 || DestVT == MVT::f64) &&
          "Unexpected value type.");
 
diff --git a/test/CodeGen/AArch64/arm64-fast-isel-conversion-fallback.ll b/test/CodeGen/AArch64/arm64-fast-isel-conversion-fallback.ll
new file mode 100644
index 00000000000..16a02de79a9
--- /dev/null
+++ b/test/CodeGen/AArch64/arm64-fast-isel-conversion-fallback.ll
@@ -0,0 +1,131 @@
+; RUN: llc -O0 -verify-machineinstrs -mtriple=arm64-eabi < %s | FileCheck --enable-var-scope %s
+
+; Test fptosi
+define i32 @fptosi_wh(half %a) nounwind ssp {
+entry:
+; CHECK-LABEL: fptosi_wh
+; CHECK: fcvt s1, h0
+; CHECK: fcvtzs [[REG:w[0-9]+]], s1
+; CHECK: mov w0, [[REG]]
+  %conv = fptosi half %a to i32
+  ret i32 %conv
+}
+
+; Test fptoui
+define i32 @fptoui_swh(half %a) nounwind ssp {
+entry:
+; CHECK-LABEL: fptoui_swh
+; CHECK: fcvt s1, h0
+; CHECK: fcvtzu [[REG:w[0-9]+]], s1
+; CHECK: mov w0, [[REG]]
+  %conv = fptoui half %a to i32
+  ret i32 %conv
+}
+
+; Test sitofp
+define half @sitofp_hw_i1(i1 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: sitofp_hw_i1
+; CHECK: sbfx w0, w0, #0, #1
+; CHECK: scvtf s0, w0
+; CHECK: fcvt  h0, s0
+  %conv = sitofp i1 %a to half
+  ret half %conv
+}
+
+; Test sitofp
+define half @sitofp_hw_i8(i8 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: sitofp_hw_i8
+; CHECK: sxtb w0, w0
+; CHECK: scvtf s0, w0
+; CHECK: fcvt  h0, s0
+  %conv = sitofp i8 %a to half
+  ret half %conv
+}
+
+; Test sitofp
+define half @sitofp_hw_i16(i16 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: sitofp_hw_i16
+; CHECK: sxth w0, w0
+; CHECK: scvtf s0, w0
+; CHECK: fcvt  h0, s0
+  %conv = sitofp i16 %a to half
+  ret half %conv
+}
+
+; Test sitofp
+define half @sitofp_hw_i32(i32 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: sitofp_hw_i32
+; CHECK: scvtf s0, w0
+; CHECK: fcvt  h0, s0
+  %conv = sitofp i32 %a to half
+  ret half %conv
+}
+
+; Test sitofp
+define half @sitofp_hx(i64 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: sitofp_hx
+; CHECK: scvtf s0, x0
+; CHECK: fcvt  h0, s0
+  %conv = sitofp i64 %a to half
+  ret half %conv
+}
+
+; Test uitofp
+define half @uitofp_hw_i1(i1 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: uitofp_hw_i1
+; CHECK: and w0, w0, #0x1
+; CHECK: ucvtf s0, w0
+; CHECK: fcvt  h0, s0
+  %conv = uitofp i1 %a to half
+  ret half %conv
+}
+
+; Test uitofp
+define half @uitofp_hw_i8(i8 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: uitofp_hw_i8
+; CHECK: and w0, w0, #0xff
+; CHECK: ucvtf s0, w0
+; CHECK: fcvt  h0, s0
+  %conv = uitofp i8 %a to half
+  ret half %conv
+}
+
+; Test uitofp
+define half @uitofp_hw_i16(i16 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: uitofp_hw_i16
+; CHECK: and w0, w0, #0xffff
+; CHECK: ucvtf s0, w0
+; CHECK: fcvt  h0, s0
+  %conv = uitofp i16 %a to half
+  ret half %conv
+}
+
+; Test uitofp
+define half @uitofp_hw_i32(i32 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: uitofp_hw_i32
+; CHECK: ucvtf s0, w0
+; CHECK: fcvt  h0, s0
+  %conv = uitofp i32 %a to half
+  ret half %conv
+}
+
+; Test uitofp
+define half @uitofp_hx(i64 %a) nounwind ssp {
+entry:
+; CHECK-LABEL: uitofp_hx
+; CHECK: ucvtf s0, x0
+; CHECK: fcvt  h0, s0
+  %conv = uitofp i64 %a to half
+  ret half %conv
+}
+
+