From 84c1c9dc38087727f285b19c438be14f4f8bd6b2 Mon Sep 17 00:00:00 2001
From: nkennedy <nkennedy@git.zephyr-software.com>
Date: Wed, 5 Nov 2014 17:23:48 +0000
Subject: [PATCH] Revert r15793 (lea/jmp combinations), causing breakage on
T&E. ok jdh8d@
Former-commit-id: d4219bb8a5ba15721a106204bbc4abb2f5d31380
---
libIRDB/test/fill_in_indtargs.cpp | 171 ------------------------------
1 file changed, 171 deletions(-)
diff --git a/libIRDB/test/fill_in_indtargs.cpp b/libIRDB/test/fill_in_indtargs.cpp
index adb7597c6..c770e7736 100644
--- a/libIRDB/test/fill_in_indtargs.cpp
+++ b/libIRDB/test/fill_in_indtargs.cpp
@@ -22,7 +22,6 @@
int odd_target_count=0;
int bad_target_count=0;
int bad_fallthrough_count=0;
-int lea_jmp_target_count=0;
using namespace libIRDB;
using namespace std;
@@ -33,7 +32,6 @@ bool is_possible_target(int p, uintptr_t addr);
set< pair <int,int> > bounds;
set<int> targets;
-set<virtual_offset_t> instruction_addresses;
set< pair< int, int> > ranges;
@@ -44,33 +42,6 @@ map< Instruction_t* , set<Instruction_t*> > preds;
void check_for_PIC_switch_table32(Instruction_t* insn, DISASM disasm, ELFIO::elfio* elfiop, const set<int>& thunk_bases);
void check_for_PIC_switch_table64(Instruction_t* insn, DISASM disasm, ELFIO::elfio* elfiop);
-void record_instruction_addresses(VariantID_t *pidp) {
- instruction_addresses.clear();
-
- for(set<File_t*>::iterator it=pidp->GetFiles().begin();
- it!=pidp->GetFiles().end();
- ++it
- )
- {
- File_t* file=*it;
- assert(file);
- FileIR_t *firp=new FileIR_t(*pidp, file);
- for(
- set<Instruction_t*>::const_iterator iit=firp->GetInstructions().begin();
- iit!=firp->GetInstructions().end();
- ++iit
- )
- {
- Instruction_t *insn=*iit;
- instruction_addresses.insert(insn->GetAddress()->GetVirtualOffset());
- }
- }
-}
-
-bool is_instruction_address(virtual_offset_t addr) {
- return instruction_addresses.find(addr) != instruction_addresses.end();
-}
-
void range(int start, int end)
{
pair<int,int> foo(start,end);
@@ -218,141 +189,6 @@ void mark_targets(FileIR_t *firp)
}
}
-
-void get_lea_instruction_targets(FileIR_t *firp)
-{
- for(
- set<Instruction_t*>::const_iterator it=firp->GetInstructions().begin();
- it!=firp->GetInstructions().end();
- ++it
- )
- {
- Instruction_t *insn=*it;
- Instruction_t *next_insn;
- DISASM insn_disasm;
- DISASM next_insn_disasm;
- int insn_instr_len = -1;
- int next_insn_instr_len = -1;
-
- insn_instr_len = insn->Disassemble(insn_disasm);
- assert(insn_instr_len==insn->GetDataBits().size());
-
- /*
- * Confirm that there is a 'next' instruction
- */
- if (!(next_insn = insn->GetFallthrough()))
- continue;
-
- /*
- * We know insn is followed by another instruction.
- */
- next_insn_instr_len = next_insn->Disassemble(next_insn_disasm);
-
- /*
- * Check if insn is an lea and next_insn is a jump
- */
- if (!strcmp(insn_disasm.Instruction.Mnemonic,"lea ") &&
- !strcmp(next_insn_disasm.Instruction.Mnemonic,"jmp "))
- {
- /*
- * Only consider the case where the lea instruction
- * stores its result in the same register used
- * by the indirect jump.
- */
- if (strcmp(insn_disasm.Argument1.ArgMnemonic,
- next_insn_disasm.Argument1.ArgMnemonic))
- continue;
-
- /*
- * From the base, the calculation will be a multiple i
- * of some value v that indexes an instruction. At
- * some multiple of that v, there won't
- * be an instruction. I.e., base + i*v will point
- * to a place that is in the middle of an instruction.
- * So we want to stop there!
- *
- * Note: Only in the case when the base and index register
- * match will this work (or the base register is zero).
- * In any other case we have insufficient information
- * to mark targets because the offset depends
- * on a register value and not an arbitrary multiple
- * of some constant. This is an assertion so that we can
- * properly notice cases that don't match!
- */
- if ((insn_disasm.Argument2.ArgType&MEMORY_TYPE) == MEMORY_TYPE)
- {
-
- int multiple = insn_disasm.Argument2.Memory.Scale;
-
- if (insn_disasm.Argument2.Memory.BaseRegister !=
- insn_disasm.Argument2.Memory.IndexRegister)
- {
- /*
- * Since they are not equal, we assert that
- * the base register is 0. However, there may
- * be places where this assertion does not
- * hold that we are still able to handle.
- * For example,
- *
- * <realloc+0x2f78> call 000189ad <realloc+0x2f7d>
- * <realloc+0x2f7d> pop %edx
- * -----
- * We know the value of edx from the "thunk"
- * -----
- * <realloc+0x2f7e> lea 0xb(%edx,%ecx,8),%ecx
- * <realloc+0x2f82> jmp *%ecx
- * -----
- * We know where the jmp is going because we know
- * each of base, offset, index and scale:
- * -----
- * <realloc+0x2f84> lea 0x0(%esi,%eiz,1),%esi
- * Here?
- * <realloc+0x2f88> or (%esi),%al
- * <realloc+0x2f8a> je 00018a17 <realloc+0x2fe7>
- * <realloc+0x2f8c> stos %al,%es:(%edi)
- * <realloc+0x2f8d> xor %eax,%eax
- * <realloc+0x2f8f> inc %esi
- * Here?
- * <realloc+0x2f90> or (%esi),%al
- * <realloc+0x2f92> je 00018a17 <realloc+0x2fe7>
- * <realloc+0x2f94> stos %al,%es:(%edi)
- * <realloc+0x2f95> xor %eax,%eax
- * <realloc+0x2f97> inc %esi
- *
- * If this assert failure bothers you, implement code
- * to handle this case.
- */
- assert(insn_disasm.Argument2.Memory.BaseRegister == 0);
- }
- else
- {
- /*
- * Scale*offset + offset = (Scale+1)*offset
- */
- multiple+=1;
- }
-
- /*
- * Start the loop by assuming that we actually jump
- * somewhere. In other words, the calculated offset
- * is not zero.
- */
- int i = insn_disasm.Argument2.Memory.Displacement + multiple;
- for (;;i+=multiple)
- {
- if (is_instruction_address(i)) {
- printf("Setting %p as possible target.\n", (void*)i);
- lea_jmp_target_count++;
- possible_target(i);
- }
- else
- break;
- }
- }
- }
- }
-}
-
void get_instruction_targets(FileIR_t *firp, ELFIO::elfio* elfiop, const set<int>& thunk_bases)
{
@@ -918,11 +754,6 @@ void fill_in_indtargs(FileIR_t* firp, elfio* elfiop)
print_targets();
cout<<"========================================="<<endl;
- /* Mark indirect targets calculated using lea. */
- get_lea_instruction_targets(firp);
- cout<<"========================================="<<endl;
- cout<<"# ATTRIBUTE lea_jmp_target_count="<<std::dec<<lea_jmp_target_count<<endl;
- cout<<"========================================="<<endl;
@@ -961,8 +792,6 @@ main(int argc, char* argv[])
cout<<"New Variant, after reading registration, is: "<<*pidp << endl;
- record_instruction_addresses(pidp);
-
for(set<File_t*>::iterator it=pidp->GetFiles().begin();
it!=pidp->GetFiles().end();
++it
--
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