[PowerPC] FastISel can't handle i1 return values when using CR bits

Under normal circumstances, use of CR bits is disabled when running at -O0, but
it is enabled by default otherwise, and if you have optnone functions, they'll
still generally be generated with crbits turned on (because nothing else turns
them off). FastISel can't handle most things dealing with i1 values when using
CR bits, and checks for that, but was not checking the return type on
functions; we can't fast-isel function calls with i1 return values either when
using CR bits for boolean values.

Fixes PR22664.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233775 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/PPCFastISel.cpp b/lib/Target/PowerPC/PPCFastISel.cpp
index fbd7b6d7f1ce775c6000eb3256d8cb23ddbb2e98..8d3f308ab963a69c60b0e9e26b6ed24495bd7f26 100644 (file)
--- a/lib/Target/PowerPC/PPCFastISel.cpp
+++ b/lib/Target/PowerPC/PPCFastISel.cpp
@@ -1444,6 +1444,9 @@ bool PPCFastISel::fastLowerCall(CallLoweringInfo &CLI) {
   else if (!isTypeLegal(RetTy, RetVT) && RetVT != MVT::i16 &&
            RetVT != MVT::i8)
     return false;
+  else if (RetVT == MVT::i1 && PPCSubTarget->useCRBits())
+    // We can't handle boolean returns when CR bits are in use.
+    return false;
 
   // FIXME: No multi-register return values yet.
   if (RetVT != MVT::isVoid && RetVT != MVT::i8 && RetVT != MVT::i16 &&

diff --git a/test/CodeGen/PowerPC/optnone-crbits-i1-ret.ll b/test/CodeGen/PowerPC/optnone-crbits-i1-ret.ll
new file mode 100644 (file)
index 0000000..745a038
--- /dev/null
+++ b/test/CodeGen/PowerPC/optnone-crbits-i1-ret.ll
@@ -0,0 +1,37 @@
+; RUN: llc < %s | FileCheck %s
+target datalayout = "E-m:e-i64:64-n32:64"
+target triple = "powerpc64-bgq-linux"
+
+declare zeroext i1 @ri1()
+declare void @se1()
+declare void @se2()
+
+define void @test() #0 {
+entry:
+  %b = call zeroext i1 @ri1()
+  br label %next
+
+; CHECK-LABEL: @test
+; CHECK: bl ri1
+; CHECK-NEXT: nop
+; CHECK: andi. 3, 3, 1
+
+next:
+  br i1 %b, label %case1, label %case2
+
+case1:
+  call void @se1()
+  br label %end
+
+case2:
+  call void @se2()
+  br label %end
+
+end:
+  ret void
+
+; CHECK: blr
+}
+
+attributes #0 = { noinline optnone }
+