Add trunc->branch support, this won't help with clang's i8->i1 truncations
for bools, but is a start.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130534 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMFastISel.cpp b/lib/Target/ARM/ARMFastISel.cpp
index 333022c..0b63838 100644
--- a/lib/Target/ARM/ARMFastISel.cpp
+++ b/lib/Target/ARM/ARMFastISel.cpp
@@ -1116,6 +1116,30 @@
FuncInfo.MBB->addSuccessor(TBB);
return true;
}
+ } else if (TruncInst *TI = dyn_cast<TruncInst>(BI->getCondition())) {
+ MVT SourceVT;
+ if (TI->hasOneUse() && TI->getParent() == I->getParent() &&
+ (isTypeLegal(TI->getOperand(0)->getType(), SourceVT))) {
+ unsigned TstOpc = isThumb ? ARM::t2TSTri : ARM::TSTri;
+ unsigned OpReg = getRegForValue(TI->getOperand(0));
+ AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+ TII.get(TstOpc))
+ .addReg(OpReg).addImm(1));
+
+ unsigned CCMode = ARMCC::NE;
+ if (FuncInfo.MBB->isLayoutSuccessor(TBB)) {
+ std::swap(TBB, FBB);
+ CCMode = ARMCC::EQ;
+ }
+
+ unsigned BrOpc = isThumb ? ARM::t2Bcc : ARM::Bcc;
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(BrOpc))
+ .addMBB(TBB).addImm(CCMode).addReg(ARM::CPSR);
+
+ FastEmitBranch(FBB, DL);
+ FuncInfo.MBB->addSuccessor(TBB);
+ return true;
+ }
}
unsigned CmpReg = getRegForValue(BI->getCondition());
@@ -1132,7 +1156,6 @@
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TstOpc))
.addReg(CmpReg).addImm(1));
-
unsigned CCMode = ARMCC::NE;
if (FuncInfo.MBB->isLayoutSuccessor(TBB)) {
std::swap(TBB, FBB);
diff --git a/test/CodeGen/ARM/fast-isel.ll b/test/CodeGen/ARM/fast-isel.ll
index dd806ec..c8637d1 100644
--- a/test/CodeGen/ARM/fast-isel.ll
+++ b/test/CodeGen/ARM/fast-isel.ll
@@ -13,4 +13,19 @@
%tmp1 = load i32* %b.addr
%add = add nsw i32 %tmp, %tmp1
ret i32 %add
-}
\ No newline at end of file
+}
+
+define void @test1(i32 %tmp) nounwind {
+entry:
+%tobool = trunc i32 %tmp to i1
+br i1 %tobool, label %if.then, label %if.end
+
+if.then: ; preds = %entry
+call void @test1(i32 0)
+br label %if.end
+
+if.end: ; preds = %if.then, %entry
+ret void
+; CHECK: test1:
+; CHECK: tst r0, #1
+}