[PowerPC] Clean up generation of ha16() / lo16() markers
When targeting the Darwin assembler, we need to generate markers ha16() and
lo16() to designate the high and low parts of a (symbolic) immediate. This
is necessary not just for plain symbols, but also for certain symbolic
expression, typically along the lines of ha16(A - B). The latter doesn't
work when simply using VariantKind flags on the symbol reference.
This is why the current back-end uses hacks (explicitly called out as such
via multiple FIXMEs) in the symbolLo/symbolHi print methods.
This patch uses target-defined MCExpr codes to represent the Darwin
ha16/lo16 constructs, following along the lines of the equivalent solution
used by the ARM back end to handle their :upper16: / :lower16: markers.
This allows us to get rid of special handling both in the symbolLo/symbolHi
print method and in the common code MCExpr::print routine. Instead, the
ha16 / lo16 markers are printed simply in a custom print routine for the
target MCExpr types. (As a result, the symbolLo/symbolHi print methods
can now replaced by a single printS16ImmOperand routine that also handles
symbolic operands.)
The patch also provides a EvaluateAsRelocatableImpl routine to handle
ha16/lo16 constructs. This is not actually used at the moment by any
in-tree code, but is provided as it makes merging into David Fang's
out-of-tree Mach-O object writer simpler.
Since there is no longer any need to treat VK_PPC_GAS_HA16 and
VK_PPC_DARWIN_HA16 differently, they are merged into a single
VK_PPC_ADDR16_HA (and likewise for the _LO16 types).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182616 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCInstrInfo.td b/lib/Target/PowerPC/PPCInstrInfo.td
index 33a5a0e..9a1a89a 100644
--- a/lib/Target/PowerPC/PPCInstrInfo.td
+++ b/lib/Target/PowerPC/PPCInstrInfo.td
@@ -459,12 +459,12 @@
let PrintMethod = "printAbsAddrOperand";
}
def symbolHi: Operand<i32> {
- let PrintMethod = "printSymbolHi";
+ let PrintMethod = "printS16ImmOperand";
let EncoderMethod = "getS16ImmEncoding";
let ParserMatchClass = PPCS16ImmAsmOperand;
}
def symbolLo: Operand<i32> {
- let PrintMethod = "printSymbolLo";
+ let PrintMethod = "printS16ImmOperand";
let EncoderMethod = "getS16ImmEncoding";
let ParserMatchClass = PPCS16ImmAsmOperand;
}