[llvm-branch-commits] [lld] 572d183 - [ELF] Add TargetInfo::adjustGotPcExpr for `R_GOT_PC` relaxations. NFC
Fangrui Song via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Wed Nov 25 08:48:07 PST 2020
Author: Fangrui Song
Date: 2020-11-25T08:43:26-08:00
New Revision: 572d18397cf0d8808ec85f9bd51471cd80266c27
URL: https://github.com/llvm/llvm-project/commit/572d18397cf0d8808ec85f9bd51471cd80266c27
DIFF: https://github.com/llvm/llvm-project/commit/572d18397cf0d8808ec85f9bd51471cd80266c27.diff
LOG: [ELF] Add TargetInfo::adjustGotPcExpr for `R_GOT_PC` relaxations. NFC
With this change, `TargetInfo::adjustRelaxExpr` is only related to TLS
relaxations and a subsequent clean-up can delete the `data` parameter.
Differential Revision: https://reviews.llvm.org/D92079
Added:
Modified:
lld/ELF/Arch/PPC64.cpp
lld/ELF/Arch/X86_64.cpp
lld/ELF/Relocations.cpp
lld/ELF/Target.cpp
lld/ELF/Target.h
Removed:
################################################################################
diff --git a/lld/ELF/Arch/PPC64.cpp b/lld/ELF/Arch/PPC64.cpp
index 8a3de2b3cbb2..a18cf9591125 100644
--- a/lld/ELF/Arch/PPC64.cpp
+++ b/lld/ELF/Arch/PPC64.cpp
@@ -384,6 +384,8 @@ class PPC64 final : public TargetInfo {
bool inBranchRange(RelType type, uint64_t src, uint64_t dst) const override;
RelExpr adjustRelaxExpr(RelType type, const uint8_t *data,
RelExpr expr) const override;
+ RelExpr adjustGotPcExpr(RelType type, int64_t addend,
+ const uint8_t *loc) const override;
void relaxGot(uint8_t *loc, const Relocation &rel,
uint64_t val) const override;
void relaxTlsGdToIe(uint8_t *loc, const Relocation &rel,
@@ -1392,20 +1394,23 @@ bool PPC64::inBranchRange(RelType type, uint64_t src, uint64_t dst) const {
RelExpr PPC64::adjustRelaxExpr(RelType type, const uint8_t *data,
RelExpr expr) const {
+ if (type != R_PPC64_GOT_TLSGD_PCREL34 && expr == R_RELAX_TLS_GD_TO_IE)
+ return R_RELAX_TLS_GD_TO_IE_GOT_OFF;
+ if (expr == R_RELAX_TLS_LD_TO_LE)
+ return R_RELAX_TLS_LD_TO_LE_ABS;
+ return expr;
+}
+
+RelExpr PPC64::adjustGotPcExpr(RelType type, int64_t addend,
+ const uint8_t *loc) const {
if ((type == R_PPC64_GOT_PCREL34 || type == R_PPC64_PCREL_OPT) &&
config->pcRelOptimize) {
// It only makes sense to optimize pld since paddi means that the address
// of the object in the GOT is required rather than the object itself.
- assert(data && "Expecting an instruction encoding here");
- if ((readPrefixedInstruction(data) & 0xfc000000) == 0xe4000000)
+ if ((readPrefixedInstruction(loc) & 0xfc000000) == 0xe4000000)
return R_PPC64_RELAX_GOT_PC;
}
-
- if (type != R_PPC64_GOT_TLSGD_PCREL34 && expr == R_RELAX_TLS_GD_TO_IE)
- return R_RELAX_TLS_GD_TO_IE_GOT_OFF;
- if (expr == R_RELAX_TLS_LD_TO_LE)
- return R_RELAX_TLS_LD_TO_LE_ABS;
- return expr;
+ return R_GOT_PC;
}
// Reference: 3.7.4.1 of the 64-bit ELF V2 abi supplement.
diff --git a/lld/ELF/Arch/X86_64.cpp b/lld/ELF/Arch/X86_64.cpp
index 93fd8ecb7c8e..618922844238 100644
--- a/lld/ELF/Arch/X86_64.cpp
+++ b/lld/ELF/Arch/X86_64.cpp
@@ -40,8 +40,8 @@ class X86_64 : public TargetInfo {
void applyJumpInstrMod(uint8_t *loc, JumpModType type,
unsigned size) const override;
- RelExpr adjustRelaxExpr(RelType type, const uint8_t *data,
- RelExpr expr) const override;
+ RelExpr adjustGotPcExpr(RelType type, int64_t addend,
+ const uint8_t *loc) const override;
void relaxGot(uint8_t *loc, const Relocation &rel,
uint64_t val) const override;
void relaxTlsGdToIe(uint8_t *loc, const Relocation &rel,
@@ -728,12 +728,12 @@ void X86_64::relocate(uint8_t *loc, const Relocation &rel, uint64_t val) const {
}
}
-RelExpr X86_64::adjustRelaxExpr(RelType type, const uint8_t *data,
- RelExpr relExpr) const {
+RelExpr X86_64::adjustGotPcExpr(RelType type, int64_t addend,
+ const uint8_t *loc) const {
if (type != R_X86_64_GOTPCRELX && type != R_X86_64_REX_GOTPCRELX)
- return relExpr;
- const uint8_t op = data[-2];
- const uint8_t modRm = data[-1];
+ return R_GOT_PC;
+ const uint8_t op = loc[-2];
+ const uint8_t modRm = loc[-1];
// FIXME: When PIC is disabled and foo is defined locally in the
// lower 32 bit address space, memory operand in mov can be converted into
@@ -748,11 +748,11 @@ RelExpr X86_64::adjustRelaxExpr(RelType type, const uint8_t *data,
// We don't support test/binop instructions without a REX prefix.
if (type == R_X86_64_GOTPCRELX)
- return relExpr;
+ return R_GOT_PC;
// Relaxation of test, adc, add, and, cmp, or, sbb, sub, xor.
// If PIC then no relaxation is available.
- return config->isPic ? relExpr : R_RELAX_GOT_PC_NOPIC;
+ return config->isPic ? R_GOT_PC : R_RELAX_GOT_PC_NOPIC;
}
// A subset of relaxations can only be applied for no-PIC. This method
diff --git a/lld/ELF/Relocations.cpp b/lld/ELF/Relocations.cpp
index abb21f1d7274..115957ffefe1 100644
--- a/lld/ELF/Relocations.cpp
+++ b/lld/ELF/Relocations.cpp
@@ -1361,9 +1361,7 @@ static void scanReloc(InputSectionBase &sec, OffsetGetter &getOffset, RelTy *&i,
// runtime, because the main executable is always at the beginning of a search
// list. We can leverage that fact.
if (!sym.isPreemptible && (!sym.isGnuIFunc() || config->zIfuncNoplt)) {
- if (expr == R_GOT_PC && !isAbsoluteValue(sym)) {
- expr = target->adjustRelaxExpr(type, relocatedAddr, expr);
- } else {
+ if (expr != R_GOT_PC) {
// The 0x8000 bit of r_addend of R_PPC_PLTREL24 is used to choose call
// stub type. It should be ignored if optimized to R_PC.
if (config->emachine == EM_PPC && expr == R_PPC32_PLTREL)
@@ -1375,6 +1373,8 @@ static void scanReloc(InputSectionBase &sec, OffsetGetter &getOffset, RelTy *&i,
type == R_HEX_GD_PLT_B22_PCREL_X ||
type == R_HEX_GD_PLT_B32_PCREL_X)))
expr = fromPlt(expr);
+ } else if (!isAbsoluteValue(sym)) {
+ expr = target->adjustGotPcExpr(type, addend, relocatedAddr);
}
}
diff --git a/lld/ELF/Target.cpp b/lld/ELF/Target.cpp
index 6abd8b452e23..324c07dc7fda 100644
--- a/lld/ELF/Target.cpp
+++ b/lld/ELF/Target.cpp
@@ -155,6 +155,11 @@ RelExpr TargetInfo::adjustRelaxExpr(RelType type, const uint8_t *data,
return expr;
}
+RelExpr TargetInfo::adjustGotPcExpr(RelType type, int64_t addend,
+ const uint8_t *data) const {
+ return R_GOT_PC;
+}
+
void TargetInfo::relaxGot(uint8_t *loc, const Relocation &rel,
uint64_t val) const {
llvm_unreachable("Should not have claimed to be relaxable");
diff --git a/lld/ELF/Target.h b/lld/ELF/Target.h
index 9399ecf526f4..d59d7422e42d 100644
--- a/lld/ELF/Target.h
+++ b/lld/ELF/Target.h
@@ -150,6 +150,8 @@ class TargetInfo {
virtual RelExpr adjustRelaxExpr(RelType type, const uint8_t *data,
RelExpr expr) const;
+ virtual RelExpr adjustGotPcExpr(RelType type, int64_t addend,
+ const uint8_t *loc) const;
virtual void relaxGot(uint8_t *loc, const Relocation &rel,
uint64_t val) const;
virtual void relaxTlsGdToIe(uint8_t *loc, const Relocation &rel,
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