forked from OSchip/llvm-project
[mips] Fix lowering load/store instruction in PIC case
If an operand of the `lw/sw` instructions is a symbol, these instructions incorrectly lowered using not-position-independent chain of commands. For PIC code we should use `lw/addiu` instructions with the `R_MIPS_GOT16` and `R_MIPS_LO16` relocations respectively. Instead of that LLVM generates position dependent code with the `R_MIPS_HI16` and `R_MIPS_LO16` relocations. This patch provides a fix for the bug by handling PIC case separately in the `MipsAsmParser::expandMemInst`. The main idea is to generate a chain of PIC instructions to load a symbol address into a register and then load the address content. The fix is not optimal and does not fix all PIC-related problems. This is a task for subsequent patches. Differential Revision: https://reviews.llvm.org/D65524 llvm-svn: 367580
This commit is contained in:
Simon Atanasyan
parent
66ce04f261
commit
0620cf11ec
|
|
@ -3625,8 +3625,25 @@ void MipsAsmParser::expandMemInst(MCInst &Inst, SMLoc IDLoc, MCStreamer &Out,
|
|||
TOut.emitRRR(isGP64bit() ? Mips::DADDu : Mips::ADDu, TmpReg, TmpReg,
|
||||
BaseReg, IDLoc, STI);
|
||||
TOut.emitRRI(Inst.getOpcode(), DstReg, TmpReg, LoOffset, IDLoc, STI);
|
||||
return;
|
||||
}
|
||||
|
||||
assert(OffsetOp.isExpr() && "expected expression operand kind");
|
||||
if (inPicMode()) {
|
||||
// FIXME:
|
||||
// a) Fix lw/sw $reg, symbol($reg) instruction expanding.
|
||||
// b) If expression includes offset (sym + number), do not
|
||||
// encode the offset into a relocation. Take it in account
|
||||
// in the last load/store instruction.
|
||||
// c) Check that immediates of R_MIPS_GOT16/R_MIPS_LO16 relocations
|
||||
// do not exceed 16-bit.
|
||||
// d) Use R_MIPS_GOT_PAGE/R_MIPS_GOT_OFST relocations instead
|
||||
// of R_MIPS_GOT_DISP in appropriate cases to reduce number
|
||||
// of GOT entries.
|
||||
expandLoadAddress(TmpReg, Mips::NoRegister, OffsetOp, !ABI.ArePtrs64bit(),
|
||||
IDLoc, Out, STI);
|
||||
TOut.emitRRI(Inst.getOpcode(), DstReg, TmpReg, 0, IDLoc, STI);
|
||||
} else {
|
||||
assert(OffsetOp.isExpr() && "expected expression operand kind");
|
||||
const MCExpr *ExprOffset = OffsetOp.getExpr();
|
||||
MCOperand LoOperand = MCOperand::createExpr(
|
||||
MipsMCExpr::create(MipsMCExpr::MEK_LO, ExprOffset, getContext()));
|
||||
|
|
|
|||
|
|
@ -50,6 +50,7 @@
|
|||
# CHECK-LE: lhu $4, 4($4)
|
||||
|
||||
# LW/SW and LDC1/SDC1 of symbol address, done by MipsAsmParser::expandMemInst():
|
||||
# NON-PIC code
|
||||
.set noat
|
||||
lw $10, symbol($4)
|
||||
# CHECK-LE: lui $10, %hi(symbol) # encoding: [A,A,0x0a,0x3c]
|
||||
|
|
@ -105,6 +106,64 @@
|
|||
# CHECK-LE: lui $1, %hi(symbol)
|
||||
# CHECK-LE: sdc1 $f0, %lo(symbol)($1)
|
||||
|
||||
# PIC code
|
||||
.option pic2
|
||||
.set noat
|
||||
lw $10, symbol($4)
|
||||
# CHECK-LE: lw $10, %got(symbol)($gp) # encoding: [A,A,0x8a,0x8f]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %got(symbol), kind: fixup_Mips_GOT
|
||||
# CHECK-LE-FIXME: addu $10, $10, $4 # encoding: [0x21,0x50,0x44,0x01]
|
||||
# CHECK-LE: lw $10, 0($10) # encoding: [0x00,0x00,0x4a,0x8d]
|
||||
.set at
|
||||
sw $10, symbol($9)
|
||||
# CHECK-LE: lw $1, %got(symbol)($gp) # encoding: [A,A,0x81,0x8f]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %got(symbol), kind: fixup_Mips_GOT
|
||||
# CHECK-LE-FIXME: addu $1, $1, $9 # encoding: [0x21,0x08,0x29,0x00]
|
||||
# CHECK-LE: sw $10, 0($1) # encoding: [0x00,0x00,0x2a,0xac]
|
||||
|
||||
lw $8, 1f+8
|
||||
# CHECK-LE: lw $8, %got(($tmp0)+8)($gp) # encoding: [A,A,0x88,0x8f]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %got(($tmp0)+8), kind: fixup_Mips_GOT
|
||||
# CHECK-LE: addiu $8, $8, %lo(($tmp0)+8) # encoding: [A,A,0x08,0x25]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %lo(($tmp0)+8), kind: fixup_Mips_LO16
|
||||
# CHECK-LE: lw $8, 0($8) # encoding: [0x00,0x00,0x08,0x8d]
|
||||
sw $8, 1f+8
|
||||
# CHECK-LE: lw $1, %got(($tmp0)+8)($gp) # encoding: [A,A,0x81,0x8f]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %got(($tmp0)+8), kind: fixup_Mips_GOT
|
||||
# CHECK-LE: addiu $1, $1, %lo(($tmp0)+8) # encoding: [A,A,0x21,0x24]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %lo(($tmp0)+8), kind: fixup_Mips_LO16
|
||||
# CHECK-LE: sw $8, 0($1) # encoding: [0x00,0x00,0x28,0xac]
|
||||
|
||||
lw $10, 655483($4)
|
||||
# CHECK-LE: lui $10, 10 # encoding: [0x0a,0x00,0x0a,0x3c]
|
||||
# CHECK-LE: addu $10, $10, $4 # encoding: [0x21,0x50,0x44,0x01]
|
||||
# CHECK-LE: lw $10, 123($10) # encoding: [0x7b,0x00,0x4a,0x8d]
|
||||
sw $10, 123456($9)
|
||||
# CHECK-LE: lui $1, 2 # encoding: [0x02,0x00,0x01,0x3c]
|
||||
# CHECK-LE: addu $1, $1, $9 # encoding: [0x21,0x08,0x29,0x00]
|
||||
# CHECK-LE: sw $10, -7616($1) # encoding: [0x40,0xe2,0x2a,0xac]
|
||||
|
||||
lw $8, symbol+8
|
||||
# CHECK-LE: lw $8, %got(symbol+8)($gp) # encoding: [A,A,0x88,0x8f]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %got(symbol+8), kind: fixup_Mips_GOT
|
||||
# CHECK-LE: addiu $8, $8, 8 # encoding: [0x08,0x00,0x08,0x25]
|
||||
# CHECK-LE: lw $8, 0($8) # encoding: [0x00,0x00,0x08,0x8d]
|
||||
sw $8, symbol+8
|
||||
# CHECK-LE: lw $1, %got(symbol+8)($gp) # encoding: [A,A,0x81,0x8f]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %got(symbol+8), kind: fixup_Mips_GOT
|
||||
# CHECK-LE: addiu $1, $1, 8 # encoding: [0x08,0x00,0x21,0x24]
|
||||
# CHECK-LE: sw $8, 0($1) # encoding: [0x00,0x00,0x28,0xac]
|
||||
|
||||
ldc1 $f0, symbol
|
||||
# CHECK-LE: lw $1, %got(symbol)($gp) # encoding: [A,A,0x81,0x8f]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %got(symbol), kind: fixup_Mips_GOT
|
||||
# CHECK-LE: ldc1 $f0, 0($1) # encoding: [0x00,0x00,0x20,0xd4]
|
||||
sdc1 $f0, symbol
|
||||
# CHECK-LE: lw $1, %got(symbol)($gp) # encoding: [A,A,0x81,0x8f]
|
||||
# CHECK-LE: # fixup A - offset: 0, value: %got(symbol), kind: fixup_Mips_GOT
|
||||
# CHECK-LE: sdc1 $f0, 0($1) # encoding: [0x00,0x00,0x20,0xf4]
|
||||
.option pic0
|
||||
|
||||
# Test BNE with an immediate as the 2nd operand.
|
||||
bne $2, 0, 1332
|
||||
# CHECK-LE: bnez $2, 1332 # encoding: [0x4d,0x01,0x40,0x14]
|
||||
|
|
|
|||
|
|
@ -466,3 +466,56 @@ sym:
|
|||
# CHECK-NEXT: dsll $4, $4, 16
|
||||
# CHECK-NEXT: daddu $4, $4, $3
|
||||
# CHECK-NEXT: lhu $4, -32764($4)
|
||||
|
||||
# LW/SW and LDC1/SDC1 of symbol address, done by MipsAsmParser::expandMemInst():
|
||||
.option pic2
|
||||
lw $10, symbol($4)
|
||||
# CHECK: ld $10, %got_disp(symbol)($gp) # encoding: [A,A,0x8a,0xdf]
|
||||
# CHECK: # fixup A - offset: 0, value: %got_disp(symbol), kind: fixup_Mips_GOT_DISP
|
||||
# CHECK-FIXME: daddu $10, $10, $4 # encoding: [0x2d,0x50,0x44,0x01]
|
||||
# CHECK: lw $10, 0($10) # encoding: [0x00,0x00,0x4a,0x8d]
|
||||
sw $10, symbol($9)
|
||||
# CHECK: ld $1, %got_disp(symbol)($gp) # encoding: [A,A,0x81,0xdf]
|
||||
# CHECK: # fixup A - offset: 0, value: %got_disp(symbol), kind: fixup_Mips_GOT_DISP
|
||||
# CHECK-FIXME: daddu $1, $1, $9 # encoding: [0x2d,0x08,0x29,0x00]
|
||||
# CHECK: sw $10, 0($1) # encoding: [0x00,0x00,0x2a,0xac]
|
||||
|
||||
lw $8, sym+8
|
||||
# CHECK: ld $8, %got_disp(sym)($gp) # encoding: [A,A,0x88,0xdf]
|
||||
# CHECK: # fixup A - offset: 0, value: %got_disp(sym), kind: fixup_Mips_GOT_DISP
|
||||
# CHECK: daddiu $8, $8, 8 # encoding: [0x08,0x00,0x08,0x65]
|
||||
# CHECK: lw $8, 0($8) # encoding: [0x00,0x00,0x08,0x8d]
|
||||
sw $8, sym+8
|
||||
# CHECK: ld $1, %got_disp(sym)($gp) # encoding: [A,A,0x81,0xdf]
|
||||
# CHECK: # fixup A - offset: 0, value: %got_disp(sym), kind: fixup_Mips_GOT_DISP
|
||||
# CHECK: daddiu $1, $1, 8 # encoding: [0x08,0x00,0x21,0x64]
|
||||
# CHECK: sw $8, 0($1) # encoding: [0x00,0x00,0x28,0xac]
|
||||
|
||||
lw $10, 655483($4)
|
||||
# CHECK: lui $10, 10 # encoding: [0x0a,0x00,0x0a,0x3c]
|
||||
# CHECK: daddu $10, $10, $4 # encoding: [0x2d,0x50,0x44,0x01]
|
||||
# CHECK: lw $10, 123($10) # encoding: [0x7b,0x00,0x4a,0x8d]
|
||||
sw $10, 123456($9)
|
||||
# CHECK: lui $1, 2 # encoding: [0x02,0x00,0x01,0x3c]
|
||||
# CHECK: daddu $1, $1, $9 # encoding: [0x2d,0x08,0x29,0x00]
|
||||
# CHECK: sw $10, -7616($1) # encoding: [0x40,0xe2,0x2a,0xac]
|
||||
|
||||
lw $8, symbol+8
|
||||
# CHECK: ld $8, %got_disp(symbol)($gp) # encoding: [A,A,0x88,0xdf]
|
||||
# CHECK: # fixup A - offset: 0, value: %got_disp(symbol), kind: fixup_Mips_GOT_DISP
|
||||
# CHECK: daddiu $8, $8, 8 # encoding: [0x08,0x00,0x08,0x65]
|
||||
# CHECK: lw $8, 0($8) # encoding: [0x00,0x00,0x08,0x8d]
|
||||
sw $8, symbol+8
|
||||
# CHECK: ld $1, %got_disp(symbol)($gp) # encoding: [A,A,0x81,0xdf]
|
||||
# CHECK: # fixup A - offset: 0, value: %got_disp(symbol), kind: fixup_Mips_GOT_DISP
|
||||
# CHECK: daddiu $1, $1, 8 # encoding: [0x08,0x00,0x21,0x64]
|
||||
# CHECK: sw $8, 0($1) # encoding: [0x00,0x00,0x28,0xac]
|
||||
|
||||
ldc1 $f0, symbol
|
||||
# CHECK: ld $1, %got_disp(symbol)($gp) # encoding: [A,A,0x81,0xdf]
|
||||
# CHECK: # fixup A - offset: 0, value: %got_disp(symbol), kind: fixup_Mips_GOT_DISP
|
||||
# CHECK: ldc1 $f0, 0($1) # encoding: [0x00,0x00,0x20,0xd4]
|
||||
sdc1 $f0, symbol
|
||||
# CHECK: ld $1, %got_disp(symbol)($gp) # encoding: [A,A,0x81,0xdf]
|
||||
# CHECK: # fixup A - offset: 0, value: %got_disp(symbol), kind: fixup_Mips_GOT_DISP
|
||||
# CHECK: sdc1 $f0, 0($1) # encoding: [0x00,0x00,0x20,0xf4]
|
||||
|
|
|
|||
Loading…
Reference in New Issue