llvm-6502/test/MC/MachO/cstexpr-gotpcrel-64.ll

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[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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; RUN: llc -mtriple=x86_64-apple-darwin %s -o %t
; RUN: FileCheck %s -check-prefix=X86 < %t
; RUN: FileCheck %s -check-prefix=X86-GOT-EQUIV < %t
[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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; GOT equivalent globals references can be replaced by the GOT entry of the
; final symbol instead.
%struct.data = type { i32, %struct.anon }
%struct.anon = type { i32, i32 }
; Check that these got equivalent symbols are never emitted.
; X86-GOT-EQUIV-NOT: L_localgotequiv
; X86-GOT-EQUIV-NOT: l_extgotequiv
[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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@localfoo = global i32 42
@localgotequiv = private unnamed_addr constant i32* @localfoo
@extfoo = external global i32
@extgotequiv = private unnamed_addr constant i32* @extfoo
; Don't replace GOT equivalent usage within instructions and emit the GOT
; equivalent since it can't be replaced by the GOT entry. @bargotequiv is
; used by an instruction inside @t0.
;
; X86: l_bargotequiv:
; X86-NEXT: .quad _extbar
[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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@extbar = external global i32
@bargotequiv = private unnamed_addr constant i32* @extbar
@table = global [4 x %struct.data] [
%struct.data { i32 1, %struct.anon { i32 2, i32 3 } },
; Test GOT equivalent usage inside nested constant arrays.
; X86: .long 5
; X86-NOT: .long _localgotequiv-(_table+20)
; X86-NEXT: .long _localfoo@GOTPCREL+4
[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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%struct.data { i32 4, %struct.anon { i32 5,
i32 trunc (i64 sub (i64 ptrtoint (i32** @localgotequiv to i64),
i64 ptrtoint (i32* getelementptr inbounds ([4 x %struct.data]* @table, i32 0, i64 1, i32 1, i32 1) to i64))
to i32)}
},
; X86: .long 5
; X86-NOT: _extgotequiv-(_table+32)
; X86-NEXT: .long _extfoo@GOTPCREL+4
[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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%struct.data { i32 4, %struct.anon { i32 5,
i32 trunc (i64 sub (i64 ptrtoint (i32** @extgotequiv to i64),
i64 ptrtoint (i32* getelementptr inbounds ([4 x %struct.data]* @table, i32 0, i64 2, i32 1, i32 1) to i64))
to i32)}
},
; Test support for arbitrary constants into the GOTPCREL offset.
; X86: .long 5
; X86-NOT: _extgotequiv-(_table+44)
; X86-NEXT: .long _extfoo@GOTPCREL+28
[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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%struct.data { i32 4, %struct.anon { i32 5,
i32 add (i32 trunc (i64 sub (i64 ptrtoint (i32** @extgotequiv to i64),
i64 ptrtoint (i32* getelementptr inbounds ([4 x %struct.data]* @table, i32 0, i64 3, i32 1, i32 1) to i64))
to i32), i32 24)}
}
], align 16
; Test multiple uses of GOT equivalents.
; X86-LABEL: _delta
; X86: .long _extfoo@GOTPCREL+4
[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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@delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @extgotequiv to i64),
i64 ptrtoint (i32* @delta to i64))
to i32)
; X86-LABEL: _deltaplus:
; X86: .long _localfoo@GOTPCREL+59
[AsmPrinter] Access pointers to globals via pcrel GOT entries Front-ends could use global unnamed_addr to hold pointers to other symbols, like @gotequivalent below: @foo = global i32 42 @gotequivalent = private unnamed_addr constant i32* @foo @delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64), i64 ptrtoint (i32* @delta to i64)) to i32) The global @delta holds a data "PC"-relative offset to @gotequivalent, an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows: .globl _foo _foo: .long 42 .globl _gotequivalent _gotequivalent: .quad _foo .globl _delta _delta: .long _gotequivalent-_delta Since unnamed_addr indicates that the address is not significant, only the content, we can optimize the case above by replacing pc-relative accesses to "GOT equivalent" globals, by a PC relative access to the GOT entry of the final symbol instead. Therefore, "delta" can contain a pc relative relocation to foo's GOT entry and we avoid the emission of "gotequivalent", yielding the assembly code below: .globl _foo _foo: .long 42 .globl _delta _delta: .long _foo@GOTPCREL+4 There are a couple of advantages of doing this: (1) Front-ends that need to emit a great deal of data to store pointers to external symbols could save space by not emitting such "got equivalent" globals and (2) IR constructs combined with this opt opens a way to represent GOT pcrel relocations by using the LLVM IR, which is something we previously had no way to express. Differential Revision: http://reviews.llvm.org/D6922 rdar://problem/18534217 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
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@deltaplus = global i32 add (i32 trunc (i64 sub (i64 ptrtoint (i32** @localgotequiv to i64),
i64 ptrtoint (i32* @deltaplus to i64))
to i32), i32 55)
define i32 @t0(i32 %a) {
%x = add i32 trunc (i64 sub (i64 ptrtoint (i32** @bargotequiv to i64),
i64 ptrtoint (i32 (i32)* @t0 to i64))
to i32), %a
ret i32 %x
}