Support three-argument instructions on x86-64.
Change-Id: I81c855cd4805d4a5016999669a0cb5261838f23a
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/35224
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
diff --git a/util/fipstools/delocate/delocate.go b/util/fipstools/delocate/delocate.go
index ce1a8b2..593abec 100644
--- a/util/fipstools/delocate/delocate.go
+++ b/util/fipstools/delocate/delocate.go
@@ -801,6 +801,8 @@
// instrCombine merges the source and destination in some fashion, for example
// a 2-operand bitwise operation.
instrCombine
+ // instrThreeArg merges two sources into a destination in some fashion.
+ instrThreeArg
instrOther
)
@@ -831,6 +833,11 @@
return instrCombine
}
+ case "sarxq", "shlxq", "shrxq":
+ if len(args) == 3 {
+ return instrThreeArg
+ }
+
case "vpbroadcastq":
if len(args) == 2 {
return instrTransformingMove
@@ -878,10 +885,24 @@
}
}
-func saveRegister(w stringWriter, avoidReg string) (wrapperFunc, string) {
- reg := "%rax"
- if reg == avoidReg {
- reg = "%rbx"
+func saveRegister(w stringWriter, avoidRegs []string) (wrapperFunc, string) {
+ candidates := []string{"%rax", "%rbx", "%rcx", "%rdx"}
+
+ var reg string
+NextCandidate:
+ for _, candidate := range candidates {
+ for _, avoid := range avoidRegs {
+ if candidate == avoid {
+ continue NextCandidate
+ }
+ }
+
+ reg = candidate
+ break
+ }
+
+ if len(reg) == 0 {
+ panic("too many excluded registers")
}
return func(k func()) {
@@ -918,6 +939,13 @@
}
}
+func threeArgCombineOp(w stringWriter, instructionName, source1, source2, dest string) wrapperFunc {
+ return func(k func()) {
+ k()
+ w.WriteString("\t" + instructionName + " " + source1 + ", " + source2 + ", " + dest + "\n")
+ }
+}
+
func isValidLEATarget(reg string) bool {
return !strings.HasPrefix(reg, "%xmm") && !strings.HasPrefix(reg, "%ymm") && !strings.HasPrefix(reg, "%zmm")
}
@@ -1033,9 +1061,6 @@
if len(offset) > 0 {
return nil, errors.New("loading from GOT with offset is unsupported")
}
- if i != 0 {
- return nil, errors.New("GOT access must be source operand")
- }
if !d.isRIPRelative(memRef) {
return nil, errors.New("GOT access must be IP-relative")
}
@@ -1048,10 +1073,15 @@
useGOT = true
}
+ classification := classifyInstruction(instructionName, argNodes)
+ if classification != instrThreeArg && i != 0 {
+ return nil, errors.New("GOT access must be source operand")
+ }
+
// Reduce the instruction to movq symbol@GOTPCREL, targetReg.
var targetReg string
var redzoneCleared bool
- switch classifyInstruction(instructionName, argNodes) {
+ switch classification {
case instrPush:
wrappers = append(wrappers, push(d.output))
targetReg = "%rax"
@@ -1073,12 +1103,36 @@
if !isValidLEATarget(targetReg) {
return nil, fmt.Errorf("cannot handle combining instructions targeting non-general registers")
}
- saveRegWrapper, tempReg := saveRegister(d.output, targetReg)
+ saveRegWrapper, tempReg := saveRegister(d.output, []string{targetReg})
redzoneCleared = true
wrappers = append(wrappers, saveRegWrapper)
wrappers = append(wrappers, combineOp(d.output, instructionName, tempReg, targetReg))
targetReg = tempReg
+ case instrThreeArg:
+ if n := len(argNodes); n != 3 {
+ return nil, fmt.Errorf("three-argument instruction has %d arguments", n)
+ }
+ if i != 0 && i != 1 {
+ return nil, errors.New("GOT access must be from soure operand")
+ }
+ targetReg = d.contents(argNodes[2])
+
+ otherSource := d.contents(argNodes[1])
+ if i == 1 {
+ otherSource = d.contents(argNodes[0])
+ }
+
+ saveRegWrapper, tempReg := saveRegister(d.output, []string{targetReg, otherSource})
+ redzoneCleared = true
+ wrappers = append(wrappers, saveRegWrapper)
+
+ if i == 0 {
+ wrappers = append(wrappers, threeArgCombineOp(d.output, instructionName, tempReg, otherSource, targetReg))
+ } else {
+ wrappers = append(wrappers, threeArgCombineOp(d.output, instructionName, otherSource, tempReg, targetReg))
+ }
+ targetReg = tempReg
default:
return nil, fmt.Errorf("Cannot rewrite GOTPCREL reference for instruction %q", instructionName)
}
@@ -1087,7 +1141,7 @@
// Sometimes the compiler will load from the GOT to an
// XMM register, which is not a valid target of an LEA
// instruction.
- saveRegWrapper, tempReg := saveRegister(d.output, "")
+ saveRegWrapper, tempReg := saveRegister(d.output, nil)
wrappers = append(wrappers, saveRegWrapper)
isAVX := strings.HasPrefix(instructionName, "v")
wrappers = append(wrappers, moveTo(d.output, targetReg, isAVX, tempReg))
diff --git a/util/fipstools/delocate/delocate_test.go b/util/fipstools/delocate/delocate_test.go
index e0ecc17..269b484 100644
--- a/util/fipstools/delocate/delocate_test.go
+++ b/util/fipstools/delocate/delocate_test.go
@@ -48,6 +48,7 @@
{"x86_64-GOTRewrite", []string{"in.s"}, "out.s"},
{"x86_64-LabelRewrite", []string{"in1.s", "in2.s"}, "out.s"},
{"x86_64-Sections", []string{"in.s"}, "out.s"},
+ {"x86_64-ThreeArg", []string{"in.s"}, "out.s"},
}
func TestDelocate(t *testing.T) {
diff --git a/util/fipstools/delocate/testdata/x86_64-ThreeArg/in.s b/util/fipstools/delocate/testdata/x86_64-ThreeArg/in.s
new file mode 100644
index 0000000..78a09de
--- /dev/null
+++ b/util/fipstools/delocate/testdata/x86_64-ThreeArg/in.s
@@ -0,0 +1,14 @@
+ .type foo, @function
+ .globl foo
+foo:
+ movq %rax, %rax
+ shrxq %rbx, kBoringSSLRSASqrtTwo@GOTPCREL(%rip), %rax
+ shrxq kBoringSSLRSASqrtTwo@GOTPCREL(%rip), %rbx, %rax
+
+
+ .type kBoringSSLRSASqrtTwo,@object # @kBoringSSLRSASqrtTwo
+ .section .rodata,"a",@progbits,unique,760
+ .globl kBoringSSLRSASqrtTwo
+ .p2align 4
+kBoringSSLRSASqrtTwo:
+ .quad -2404814165548301886 # 0xdea06241f7aa81c2
diff --git a/util/fipstools/delocate/testdata/x86_64-ThreeArg/out.s b/util/fipstools/delocate/testdata/x86_64-ThreeArg/out.s
new file mode 100644
index 0000000..7ad8f76
--- /dev/null
+++ b/util/fipstools/delocate/testdata/x86_64-ThreeArg/out.s
@@ -0,0 +1,114 @@
+.text
+.file 1 "inserted_by_delocate.c"
+.loc 1 1 0
+BORINGSSL_bcm_text_start:
+ .type foo, @function
+ .globl foo
+.Lfoo_local_target:
+foo:
+ movq %rax, %rax
+# WAS shrxq %rbx, kBoringSSLRSASqrtTwo@GOTPCREL(%rip), %rax
+ leaq -128(%rsp), %rsp
+ pushq %rcx
+ leaq .LkBoringSSLRSASqrtTwo_local_target(%rip), %rcx
+ shrxq %rbx, %rcx, %rax
+ popq %rcx
+ leaq 128(%rsp), %rsp
+# WAS shrxq kBoringSSLRSASqrtTwo@GOTPCREL(%rip), %rbx, %rax
+ leaq -128(%rsp), %rsp
+ pushq %rcx
+ leaq .LkBoringSSLRSASqrtTwo_local_target(%rip), %rcx
+ shrxq %rcx, %rbx, %rax
+ popq %rcx
+ leaq 128(%rsp), %rsp
+
+
+ .type kBoringSSLRSASqrtTwo,@object # @kBoringSSLRSASqrtTwo
+# WAS .section .rodata,"a",@progbits,unique,760
+.text
+ .globl kBoringSSLRSASqrtTwo
+ .p2align 4
+.LkBoringSSLRSASqrtTwo_local_target:
+kBoringSSLRSASqrtTwo:
+ .quad -2404814165548301886 # 0xdea06241f7aa81c2
+.text
+.loc 1 2 0
+BORINGSSL_bcm_text_end:
+.type OPENSSL_ia32cap_get, @function
+.globl OPENSSL_ia32cap_get
+.LOPENSSL_ia32cap_get_local_target:
+OPENSSL_ia32cap_get:
+ leaq OPENSSL_ia32cap_P(%rip), %rax
+ ret
+.extern OPENSSL_ia32cap_P
+.type OPENSSL_ia32cap_addr_delta, @object
+.size OPENSSL_ia32cap_addr_delta, 8
+OPENSSL_ia32cap_addr_delta:
+.quad OPENSSL_ia32cap_P-OPENSSL_ia32cap_addr_delta
+.type BORINGSSL_bcm_text_hash, @object
+.size BORINGSSL_bcm_text_hash, 64
+BORINGSSL_bcm_text_hash:
+.byte 0xae
+.byte 0x2c
+.byte 0xea
+.byte 0x2a
+.byte 0xbd
+.byte 0xa6
+.byte 0xf3
+.byte 0xec
+.byte 0x97
+.byte 0x7f
+.byte 0x9b
+.byte 0xf6
+.byte 0x94
+.byte 0x9a
+.byte 0xfc
+.byte 0x83
+.byte 0x68
+.byte 0x27
+.byte 0xcb
+.byte 0xa0
+.byte 0xa0
+.byte 0x9f
+.byte 0x6b
+.byte 0x6f
+.byte 0xde
+.byte 0x52
+.byte 0xcd
+.byte 0xe2
+.byte 0xcd
+.byte 0xff
+.byte 0x31
+.byte 0x80
+.byte 0xa2
+.byte 0xd4
+.byte 0xc3
+.byte 0x66
+.byte 0xf
+.byte 0xc2
+.byte 0x6a
+.byte 0x7b
+.byte 0xf4
+.byte 0xbe
+.byte 0x39
+.byte 0xa2
+.byte 0xd7
+.byte 0x25
+.byte 0xdb
+.byte 0x21
+.byte 0x98
+.byte 0xe9
+.byte 0xd5
+.byte 0x53
+.byte 0xbf
+.byte 0x5c
+.byte 0x32
+.byte 0x6
+.byte 0x83
+.byte 0x34
+.byte 0xc
+.byte 0x65
+.byte 0x89
+.byte 0x52
+.byte 0xbd
+.byte 0x1f
