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@@ -33,7 +33,7 @@
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//
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-// The compact unwind endoding is a 32-bit value which encoded in an
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+// The compact unwind encoding is a 32-bit value which encoded in an
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// architecture specific way, which registers to restore from where, and how
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// to unwind out of the function.
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//
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@@ -108,7 +108,7 @@ enum {
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// are encoded in the UNWIND_X86_EBP_FRAME_REGISTERS bits as five 3-bit entries.
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// Each entry contains which register to restore.
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// UNWIND_X86_MODE_STACK_IMMD:
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-// A "frameless" (EBP not used as frame pointer) function with a small
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+// A "frameless" (EBP not used as frame pointer) function with a small
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// constant stack size. To return, a constant (encoded in the compact
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// unwind encoding) is added to the ESP. Then the return is done by
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// popping the stack into the pc.
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@@ -116,19 +116,19 @@ enum {
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// on the stack immediately after the return address. The stack_size/4 is
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// encoded in the UNWIND_X86_FRAMELESS_STACK_SIZE (max stack size is 1024).
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// The number of registers saved is encoded in UNWIND_X86_FRAMELESS_STACK_REG_COUNT.
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-// UNWIND_X86_FRAMELESS_STACK_REG_PERMUTATION constains which registers were
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+// UNWIND_X86_FRAMELESS_STACK_REG_PERMUTATION contains which registers were
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// saved and their order.
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// UNWIND_X86_MODE_STACK_IND:
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-// A "frameless" (EBP not used as frame pointer) function large constant
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+// A "frameless" (EBP not used as frame pointer) function large constant
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// stack size. This case is like the previous, except the stack size is too
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-// large to encode in the compact unwind encoding. Instead it requires that
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-// the function contains "subl $nnnnnnnn,ESP" in its prolog. The compact
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+// large to encode in the compact unwind encoding. Instead it requires that
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+// the function contains "subl $nnnnnnnn,ESP" in its prolog. The compact
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// encoding contains the offset to the nnnnnnnn value in the function in
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-// UNWIND_X86_FRAMELESS_STACK_SIZE.
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+// UNWIND_X86_FRAMELESS_STACK_SIZE.
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// UNWIND_X86_MODE_DWARF:
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// No compact unwind encoding is available. Instead the low 24-bits of the
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// compact encoding is the offset of the DWARF FDE in the __eh_frame section.
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-// This mode is never used in object files. It is only generated by the
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+// This mode is never used in object files. It is only generated by the
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// linker in final linked images which have only DWARF unwind info for a
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// function.
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//
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@@ -233,36 +233,36 @@ enum {
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// For x86_64 there are four modes for the compact unwind encoding:
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// UNWIND_X86_64_MODE_RBP_FRAME:
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// RBP based frame where RBP is push on stack immediately after return address,
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-// then RSP is moved to RBP. Thus, to unwind RSP is restored with the current
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-// EPB value, then RBP is restored by popping off the stack, and the return
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+// then RSP is moved to RBP. Thus, to unwind RSP is restored with the current
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+// EPB value, then RBP is restored by popping off the stack, and the return
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// is done by popping the stack once more into the pc.
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// All non-volatile registers that need to be restored must have been saved
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-// in a small range in the stack that starts RBP-8 to RBP-2040. The offset/8
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+// in a small range in the stack that starts RBP-8 to RBP-2040. The offset/8
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// is encoded in the UNWIND_X86_64_RBP_FRAME_OFFSET bits. The registers saved
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// are encoded in the UNWIND_X86_64_RBP_FRAME_REGISTERS bits as five 3-bit entries.
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-// Each entry contains which register to restore.
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+// Each entry contains which register to restore.
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// UNWIND_X86_64_MODE_STACK_IMMD:
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-// A "frameless" (RBP not used as frame pointer) function with a small
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-// constant stack size. To return, a constant (encoded in the compact
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-// unwind encoding) is added to the RSP. Then the return is done by
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+// A "frameless" (RBP not used as frame pointer) function with a small
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+// constant stack size. To return, a constant (encoded in the compact
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+// unwind encoding) is added to the RSP. Then the return is done by
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// popping the stack into the pc.
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// All non-volatile registers that need to be restored must have been saved
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// on the stack immediately after the return address. The stack_size/8 is
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// encoded in the UNWIND_X86_64_FRAMELESS_STACK_SIZE (max stack size is 2048).
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// The number of registers saved is encoded in UNWIND_X86_64_FRAMELESS_STACK_REG_COUNT.
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-// UNWIND_X86_64_FRAMELESS_STACK_REG_PERMUTATION constains which registers were
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-// saved and their order.
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+// UNWIND_X86_64_FRAMELESS_STACK_REG_PERMUTATION contains which registers were
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+// saved and their order.
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// UNWIND_X86_64_MODE_STACK_IND:
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-// A "frameless" (RBP not used as frame pointer) function large constant
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+// A "frameless" (RBP not used as frame pointer) function large constant
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// stack size. This case is like the previous, except the stack size is too
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-// large to encode in the compact unwind encoding. Instead it requires that
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-// the function contains "subq $nnnnnnnn,RSP" in its prolog. The compact
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+// large to encode in the compact unwind encoding. Instead it requires that
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+// the function contains "subq $nnnnnnnn,RSP" in its prolog. The compact
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// encoding contains the offset to the nnnnnnnn value in the function in
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-// UNWIND_X86_64_FRAMELESS_STACK_SIZE.
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+// UNWIND_X86_64_FRAMELESS_STACK_SIZE.
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// UNWIND_X86_64_MODE_DWARF:
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// No compact unwind encoding is available. Instead the low 24-bits of the
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// compact encoding is the offset of the DWARF FDE in the __eh_frame section.
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-// This mode is never used in object files. It is only generated by the
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+// This mode is never used in object files. It is only generated by the
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// linker in final linked images which have only DWARF unwind info for a
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// function.
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//
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@@ -307,20 +307,20 @@ enum {
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// This is a standard arm64 prolog where FP/LR are immediately pushed on the
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// stack, then SP is copied to FP. If there are any non-volatile registers
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// saved, then are copied into the stack frame in pairs in a contiguous
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-// range right below the saved FP/LR pair. Any subset of the five X pairs
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+// range right below the saved FP/LR pair. Any subset of the five X pairs
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// and four D pairs can be saved, but the memory layout must be in register
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-// number order.
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+// number order.
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// UNWIND_ARM64_MODE_FRAMELESS:
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-// A "frameless" leaf function, where FP/LR are not saved. The return address
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+// A "frameless" leaf function, where FP/LR are not saved. The return address
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// remains in LR throughout the function. If any non-volatile registers
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// are saved, they must be pushed onto the stack before any stack space is
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// allocated for local variables. The stack sized (including any saved
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-// non-volatile registers) divided by 16 is encoded in the bits
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+// non-volatile registers) divided by 16 is encoded in the bits
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// UNWIND_ARM64_FRAMELESS_STACK_SIZE_MASK.
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// UNWIND_ARM64_MODE_DWARF:
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// No compact unwind encoding is available. Instead the low 24-bits of the
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// compact encoding is the offset of the DWARF FDE in the __eh_frame section.
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-// This mode is never used in object files. It is only generated by the
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+// This mode is never used in object files. It is only generated by the
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// linker in final linked images which have only DWARF unwind info for a
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// function.
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//
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@@ -337,19 +337,19 @@ enum {
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//
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// A compiler can generated compact unwind information for a function by adding
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-// a "row" to the __LD,__compact_unwind section. This section has the
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-// S_ATTR_DEBUG bit set, so the section will be ignored by older linkers.
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-// It is removed by the new linker, so never ends up in final executables.
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-// This section is a table, initially with one row per function (that needs
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+// a "row" to the __LD,__compact_unwind section. This section has the
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+// S_ATTR_DEBUG bit set, so the section will be ignored by older linkers.
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+// It is removed by the new linker, so never ends up in final executables.
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+// This section is a table, initially with one row per function (that needs
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// unwind info). The table columns and some conceptual entries are:
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//
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// range-start pointer to start of function/range
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-// range-length
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-// compact-unwind-encoding 32-bit encoding
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+// range-length
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+// compact-unwind-encoding 32-bit encoding
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// personality-function or zero if no personality function
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// lsda or zero if no LSDA data
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//
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-// The length and encoding fields are 32-bits. The other are all pointer sized.
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+// The length and encoding fields are 32-bits. The other are all pointer sized.
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//
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// In x86_64 assembly, these entry would look like:
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//
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@@ -372,23 +372,23 @@ enum {
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// .quad except_tab1
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//
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//
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-// Notes: There is no need for any labels in the the __compact_unwind section.
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-// The use of the .set directive is to force the evaluation of the
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+// Notes: There is no need for any labels in the __compact_unwind section.
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+// The use of the .set directive is to force the evaluation of the
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// range-length at assembly time, instead of generating relocations.
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//
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-// To support future compiler optimizations where which non-volatile registers
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+// To support future compiler optimizations where which non-volatile registers
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// are saved changes within a function (e.g. delay saving non-volatiles until
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// necessary), there can by multiple lines in the __compact_unwind table for one
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-// function, each with a different (non-overlapping) range and each with
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-// different compact unwind encodings that correspond to the non-volatiles
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+// function, each with a different (non-overlapping) range and each with
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+// different compact unwind encodings that correspond to the non-volatiles
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// saved at that range of the function.
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//
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// If a particular function is so wacky that there is no compact unwind way
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-// to encode it, then the compiler can emit traditional DWARF unwind info.
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+// to encode it, then the compiler can emit traditional DWARF unwind info.
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// The runtime will use which ever is available.
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//
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-// Runtime support for compact unwind encodings are only available on 10.6
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-// and later. So, the compiler should not generate it when targeting pre-10.6.
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+// Runtime support for compact unwind encodings are only available on 10.6
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+// and later. So, the compiler should not generate it when targeting pre-10.6.
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@@ -402,7 +402,7 @@ enum {
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//
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// The __TEXT,__unwind_info section is laid out for an efficient two level lookup.
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// The header of the section contains a coarse index that maps function address
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-// to the page (4096 byte block) containing the unwind info for that function.
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+// to the page (4096 byte block) containing the unwind info for that function.
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//
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#define UNWIND_SECTION_VERSION 1
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dtorilov