From d0c435c23c6dacb72964f3ce8c8cb814b248e872 Mon Sep 17 00:00:00 2001
From: Jim Grosbach <grosbach@apple.com>
Date: Fri, 16 Sep 2011 22:58:42 +0000
Subject: [PATCH] Thumb2 assembly parsing and encoding for SUB(immediate).
llvm-svn: 139966
---
llvm/lib/Target/ARM/ARMInstrThumb.td | 6 ++--
llvm/lib/Target/ARM/ARMInstrThumb2.td | 11 ++++++++
.../lib/Target/ARM/AsmParser/ARMAsmParser.cpp | 19 ++++++++++---
llvm/test/MC/ARM/basic-thumb2-instructions.s | 28 +++++++++++++++++++
4 files changed, 57 insertions(+), 7 deletions(-)
diff --git a/llvm/lib/Target/ARM/ARMInstrThumb.td b/llvm/lib/Target/ARM/ARMInstrThumb.td
index f8198c869467..a49f9880797c 100644
--- a/llvm/lib/Target/ARM/ARMInstrThumb.td
+++ b/llvm/lib/Target/ARM/ARMInstrThumb.td
@@ -1145,7 +1145,7 @@ def tSBC : // A8.6.151
// Subtract immediate
def tSUBi3 : // A8.6.210 T1
- T1sIGenEncodeImm<0b01111, (outs tGPR:$Rd), (ins tGPR:$Rm, i32imm:$imm3),
+ T1sIGenEncodeImm<0b01111, (outs tGPR:$Rd), (ins tGPR:$Rm, imm0_7:$imm3),
IIC_iALUi,
"sub", "\t$Rd, $Rm, $imm3",
[(set tGPR:$Rd, (add tGPR:$Rm, imm0_7_neg:$imm3))]> {
@@ -1154,8 +1154,8 @@ def tSUBi3 : // A8.6.210 T1
}
def tSUBi8 : // A8.6.210 T2
- T1sItGenEncodeImm<{1,1,1,?,?}, (outs tGPR:$Rdn), (ins tGPR:$Rn, i32imm:$imm8),
- IIC_iALUi,
+ T1sItGenEncodeImm<{1,1,1,?,?}, (outs tGPR:$Rdn),
+ (ins tGPR:$Rn, imm0_255:$imm8), IIC_iALUi,
"sub", "\t$Rdn, $imm8",
[(set tGPR:$Rdn, (add tGPR:$Rn, imm8_255_neg:$imm8))]>;
diff --git a/llvm/lib/Target/ARM/ARMInstrThumb2.td b/llvm/lib/Target/ARM/ARMInstrThumb2.td
index cf157c583638..5aec45ed9d78 100644
--- a/llvm/lib/Target/ARM/ARMInstrThumb2.td
+++ b/llvm/lib/Target/ARM/ARMInstrThumb2.td
@@ -3810,6 +3810,17 @@ def : t2InstAlias<"add${s}${p} $Rd, $Rn, $ShiftedRm",
(t2ADDrs rGPR:$Rd, GPRnopc:$Rn, t2_so_reg:$ShiftedRm,
pred:$p, cc_out:$s)>;
+// Aliases for SUB without the ".w" optional width specifier.
+def : t2InstAlias<"sub${s}${p} $Rd, $Rn, $imm",
+ (t2SUBri rGPR:$Rd, GPRnopc:$Rn, t2_so_imm:$imm, pred:$p, cc_out:$s)>;
+def : t2InstAlias<"sub${p} $Rd, $Rn, $imm",
+ (t2SUBri12 rGPR:$Rd, GPR:$Rn, imm0_4095:$imm, pred:$p)>;
+def : t2InstAlias<"sub${s}${p} $Rd, $Rn, $Rm",
+ (t2SUBrr rGPR:$Rd, GPRnopc:$Rn, rGPR:$Rm, pred:$p, cc_out:$s)>;
+def : t2InstAlias<"sub${s}${p} $Rd, $Rn, $ShiftedRm",
+ (t2SUBrs rGPR:$Rd, GPRnopc:$Rn, t2_so_reg:$ShiftedRm,
+ pred:$p, cc_out:$s)>;
+
// Alias for compares without the ".w" optional width specifier.
def : t2InstAlias<"cmn${p} $Rn, $Rm",
(t2CMNzrr GPRnopc:$Rn, rGPR:$Rm, pred:$p)>;
diff --git a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index 32c2a6cdf2b1..30bed29949cb 100644
--- a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -3249,7 +3249,9 @@ bool ARMAsmParser::shouldOmitCCOutOperand(StringRef Mnemonic,
// when it's an ADD Rdm, SP, {Rdm|#imm0_255} instruction. We do
// have to check the immediate range here since Thumb2 has a variant
// that can handle a different range and has a cc_out operand.
- if (isThumb() && Mnemonic == "add" && Operands.size() == 6 &&
+ if (((isThumb() && Mnemonic == "add") ||
+ (isThumbTwo() && Mnemonic == "sub")) &&
+ Operands.size() == 6 &&
static_cast<ARMOperand*>(Operands[3])->isReg() &&
static_cast<ARMOperand*>(Operands[4])->isReg() &&
static_cast<ARMOperand*>(Operands[4])->getReg() == ARM::SP &&
@@ -3257,12 +3259,13 @@ bool ARMAsmParser::shouldOmitCCOutOperand(StringRef Mnemonic,
(static_cast<ARMOperand*>(Operands[5])->isReg() ||
static_cast<ARMOperand*>(Operands[5])->isImm0_1020s4()))
return true;
- // For Thumb2, add immediate does not have a cc_out operand for the
- // imm0_4096 variant. That's the least-preferred variant when
+ // For Thumb2, add/sub immediate does not have a cc_out operand for the
+ // imm0_4095 variant. That's the least-preferred variant when
// selecting via the generic "add" mnemonic, so to know that we
// should remove the cc_out operand, we have to explicitly check that
// it's not one of the other variants. Ugh.
- if (isThumbTwo() && Mnemonic == "add" && Operands.size() == 6 &&
+ if (isThumbTwo() && (Mnemonic == "add" || Mnemonic == "sub") &&
+ Operands.size() == 6 &&
static_cast<ARMOperand*>(Operands[3])->isReg() &&
static_cast<ARMOperand*>(Operands[4])->isReg() &&
static_cast<ARMOperand*>(Operands[5])->isImm()) {
@@ -3750,6 +3753,14 @@ processInstruction(MCInst &Inst,
if (Inst.getOperand(3).getImm() < 8 && Operands.size() == 6)
Inst.setOpcode(ARM::tADDi3);
break;
+ case ARM::tSUBi8:
+ // If the immediate is in the range 0-7, we want tADDi3 iff Rd was
+ // explicitly specified. From the ARM ARM: "Encoding T1 is preferred
+ // to encoding T2 if <Rd> is specified and encoding T2 is preferred
+ // to encoding T1 if <Rd> is omitted."
+ if (Inst.getOperand(3).getImm() < 8 && Operands.size() == 6)
+ Inst.setOpcode(ARM::tSUBi3);
+ break;
case ARM::tB:
// A Thumb conditional branch outside of an IT block is a tBcc.
if (Inst.getOperand(1).getImm() != ARMCC::AL && !inITBlock())
diff --git a/llvm/test/MC/ARM/basic-thumb2-instructions.s b/llvm/test/MC/ARM/basic-thumb2-instructions.s
index 3d86850ced81..7f08d480b2b7 100644
--- a/llvm/test/MC/ARM/basic-thumb2-instructions.s
+++ b/llvm/test/MC/ARM/basic-thumb2-instructions.s
@@ -2390,6 +2390,34 @@ _func:
@ CHECK: strt r1, [r8, #255] @ encoding: [0x48,0xf8,0xff,0x1e]
+@------------------------------------------------------------------------------
+@ SUB (immediate)
+@------------------------------------------------------------------------------
+ itet eq
+ subeq r1, r2, #4
+ subwne r5, r3, #1023
+ subeq r4, r5, #293
+ sub r2, sp, #1024
+ sub r2, r8, #0xff00
+ sub r2, r3, #257
+ subw r2, r3, #257
+ sub r12, r6, #0x100
+ subw r12, r6, #0x100
+ subs r1, r2, #0x1f0
+
+@ CHECK: itet eq @ encoding: [0x0a,0xbf]
+@ CHECK: subeq r1, r2, #4 @ encoding: [0x11,0x1f]
+@ CHECK: subwne r5, r3, #1023 @ encoding: [0xa3,0xf2,0xff,0x35]
+@ CHECK: subweq r4, r5, #293 @ encoding: [0xa5,0xf2,0x25,0x14]
+@ CHECK: sub.w r2, sp, #1024 @ encoding: [0xad,0xf5,0x80,0x62]
+@ CHECK: sub.w r2, r8, #65280 @ encoding: [0xa8,0xf5,0x7f,0x42]
+@ CHECK: subw r2, r3, #257 @ encoding: [0xa3,0xf2,0x01,0x12]
+@ CHECK: subw r2, r3, #257 @ encoding: [0xa3,0xf2,0x01,0x12]
+@ CHECK: sub.w r12, r6, #256 @ encoding: [0xa6,0xf5,0x80,0x7c]
+@ CHECK: subw r12, r6, #256 @ encoding: [0xa6,0xf2,0x00,0x1c]
+@ CHECK: subs.w r1, r2, #496 @ encoding: [0xb2,0xf5,0xf8,0x71]
+
+
@------------------------------------------------------------------------------
@ SUB (register)
@------------------------------------------------------------------------------