From d14e51806b0214560ec99b5d3ce797f5fa3f7522 Mon Sep 17 00:00:00 2001
From: Qiu Chaofan <qiucofan@cn.ibm.com>
Date: Tue, 3 Nov 2020 11:17:11 +0800
Subject: [PATCH] [PowerPC] Skip IEEE 128-bit FP type in FastISel

Vector types, quadword integers and f128 currently cannot be handled in
FastISel. We did not skip f128 type in lowering arguments, which causes
a crash. This patch will fix it.

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D90206
---
 llvm/lib/Target/PowerPC/PPCFastISel.cpp       |  5 ++++-
 llvm/test/CodeGen/PowerPC/f128-passByValue.ll | 29 +++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Target/PowerPC/PPCFastISel.cpp b/llvm/lib/Target/PowerPC/PPCFastISel.cpp
index 9edbf5f..85ae195 100644
--- a/llvm/lib/Target/PowerPC/PPCFastISel.cpp
+++ b/llvm/lib/Target/PowerPC/PPCFastISel.cpp
@@ -1626,7 +1626,10 @@ bool PPCFastISel::fastLowerCall(CallLoweringInfo &CLI) {
     if (!isTypeLegal(ArgTy, ArgVT) && ArgVT != MVT::i16 && ArgVT != MVT::i8)
       return false;
 
-    if (ArgVT.isVector())
+    // FIXME: FastISel cannot handle non-simple types yet, including 128-bit FP
+    // types, which is passed through vector register. Skip these types and
+    // fallback to default SelectionDAG based selection.
+    if (ArgVT.isVector() || ArgVT == MVT::f128)
       return false;
 
     unsigned Arg = getRegForValue(ArgValue);
diff --git a/llvm/test/CodeGen/PowerPC/f128-passByValue.ll b/llvm/test/CodeGen/PowerPC/f128-passByValue.ll
index f4bdd60..0a8fc1b0 100644
--- a/llvm/test/CodeGen/PowerPC/f128-passByValue.ll
+++ b/llvm/test/CodeGen/PowerPC/f128-passByValue.ll
@@ -266,3 +266,32 @@ entry:
   store double %conv1, double* %d1, align 8
   ret void
 }
+
+; Function Attrs: noinline optnone
+define signext i32 @noopt_call_crash() #0 {
+; CHECK-LABEL: noopt_call_crash:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    mflr r0
+; CHECK-NEXT:    std r0, 16(r1)
+; CHECK-NEXT:    stdu r1, -96(r1)
+; CHECK-NEXT:    .cfi_def_cfa_offset 96
+; CHECK-NEXT:    .cfi_offset lr, 16
+; CHECK-NEXT:    bl in
+; CHECK-NEXT:    nop
+; CHECK-NEXT:    bl out
+; CHECK-NEXT:    nop
+; CHECK-NEXT:    li r3, 0
+; CHECK-NEXT:    addi r1, r1, 96
+; CHECK-NEXT:    ld r0, 16(r1)
+; CHECK-NEXT:    mtlr r0
+; CHECK-NEXT:    blr
+entry:
+  %call = call fp128 @in()
+  call void @out(fp128 %call)
+  ret i32 0
+}
+
+declare void @out(fp128)
+declare fp128 @in()
+
+attributes #0 = { noinline optnone }
-- 
2.7.4