Fix eabi calling convention when a 64 bit value shadows r3.
Without this what was happening was:
* R3 is not marked as "used"
* ARM backend thinks it has to save it to the stack because of vaarg
* Offset computation correctly ignores it
* Offsets are wrong
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110446 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/CodeGen/CallingConvLower.h b/include/llvm/CodeGen/CallingConvLower.h
index 7911907..6fb8436 100644
--- a/include/llvm/CodeGen/CallingConvLower.h
+++ b/include/llvm/CodeGen/CallingConvLower.h
@@ -275,6 +275,12 @@
return Result;
}
+ /// Version of AllocateStack with extra register to be shadowed.
+ unsigned AllocateStack(unsigned Size, unsigned Align, unsigned ShadowReg) {
+ MarkAllocated(ShadowReg);
+ return AllocateStack(Size, Align);
+ }
+
// HandleByVal - Allocate a stack slot large enough to pass an argument by
// value. The size and alignment information of the argument is encoded in its
// parameter attribute.
diff --git a/include/llvm/Target/TargetCallingConv.td b/include/llvm/Target/TargetCallingConv.td
index ceaeb0b..35b6482 100644
--- a/include/llvm/Target/TargetCallingConv.td
+++ b/include/llvm/Target/TargetCallingConv.td
@@ -89,6 +89,13 @@
int Align = align;
}
+/// CCAssignToStackWithShadow - Same as CCAssignToStack, but with a register
+/// to be shadowed.
+class CCAssignToStackWithShadow<int size, int align, Register reg> :
+ CCAssignToStack<size, align> {
+ Register ShadowReg = reg;
+}
+
/// CCPassByVal - This action always matches: it assigns the value to a stack
/// slot to implement ByVal aggregate parameter passing. Size and alignment
/// specify the minimum size and alignment for the stack slot.
diff --git a/lib/Target/ARM/ARMCallingConv.td b/lib/Target/ARM/ARMCallingConv.td
index 8fdb07f..5c5100f 100644
--- a/lib/Target/ARM/ARMCallingConv.td
+++ b/lib/Target/ARM/ARMCallingConv.td
@@ -68,7 +68,7 @@
"ArgFlags.getOrigAlign() != 8",
CCAssignToReg<[R0, R1, R2, R3]>>>,
- CCIfType<[i32], CCIfAlign<"8", CCAssignToStack<4, 8>>>,
+ CCIfType<[i32], CCIfAlign<"8", CCAssignToStackWithShadow<4, 8, R3>>>,
CCIfType<[i32, f32], CCAssignToStack<4, 4>>,
CCIfType<[f64], CCAssignToStack<8, 8>>,
CCIfType<[v2f64], CCAssignToStack<16, 8>>
diff --git a/test/CodeGen/ARM/arguments.ll b/test/CodeGen/ARM/arguments.ll
index 83b4d6e..bb7853e 100644
--- a/test/CodeGen/ARM/arguments.ll
+++ b/test/CodeGen/ARM/arguments.ll
@@ -24,6 +24,20 @@
ret i32 %.0
}
+; test that on gnueabi a 64 bit value at this position will cause r3 to go
+; unused and the value stored in [sp]
+; ELF: f3:
+; ELF: ldr r0, [sp]
+; ELF-NEXT: mov pc, lr
+; DARWIN: f3:
+; DARWIN: mov r0, r3
+; DARWIN-NEXT: mov pc, lr
+define i32 @f3(i32 %i, i32 %j, i32 %k, i64 %l, ...) {
+entry:
+ %0 = trunc i64 %l to i32
+ ret i32 %0
+}
+
declare i32 @g1(i64)
declare i32 @g2(i32 %i, ...)
diff --git a/utils/TableGen/CallingConvEmitter.cpp b/utils/TableGen/CallingConvEmitter.cpp
index 28ba2ed..7643609 100644
--- a/utils/TableGen/CallingConvEmitter.cpp
+++ b/utils/TableGen/CallingConvEmitter.cpp
@@ -169,6 +169,8 @@
else
O << "\n" << IndentStr << " State.getTarget().getTargetData()"
"->getABITypeAlignment(LocVT.getTypeForEVT(State.getContext()))";
+ if (Action->isSubClassOf("CCAssignToStackWithShadow"))
+ O << ", " << getQualifiedName(Action->getValueAsDef("ShadowReg"));
O << ");\n" << IndentStr
<< "State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset"
<< Counter << ", LocVT, LocInfo));\n";