[compiler-rt] r277683 - [compiler-rt][XRay] Stash xmm registers in the trampolines

[Dean Michael Berris via llvm-commits]

Author: dberris
Date: Wed Aug  3 19:09:35 2016
New Revision: 277683

URL: http://llvm.org/viewvc/llvm-project?rev=277683&view=rev
Log:
[compiler-rt][XRay] Stash xmm registers in the trampolines

We now stash and restore the xmm registers in the trampolines so that
log handlers don't need to worry about clobbering these registers.

In response to comments in D21612.

Reviewers: rSerge, eugenis, echristo, rnk

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D23051

Modified:
    compiler-rt/trunk/lib/xray/xray_trampoline_x86.S

Modified: compiler-rt/trunk/lib/xray/xray_trampoline_x86.S
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/xray/xray_trampoline_x86.S?rev=277683&r1=277682&r2=277683&view=diff
==============================================================================
--- compiler-rt/trunk/lib/xray/xray_trampoline_x86.S (original)
+++ compiler-rt/trunk/lib/xray/xray_trampoline_x86.S Wed Aug  3 19:09:35 2016
@@ -24,7 +24,15 @@ __xray_FunctionEntry:
   // Save caller provided registers before doing any actual work.
 	pushq %rbp
 	.cfi_def_cfa_offset 16
-	subq $72, %rsp
+	subq $200, %rsp
+	movupd	%xmm0, 184(%rsp)
+	movupd	%xmm1, 168(%rsp)
+	movupd	%xmm2, 152(%rsp)
+	movupd	%xmm3, 136(%rsp)
+	movupd	%xmm4, 120(%rsp)
+	movupd	%xmm5, 104(%rsp)
+	movupd	%xmm6, 88(%rsp)
+	movupd	%xmm7, 72(%rsp)
 	movq	%rdi, 64(%rsp)
 	movq  %rax, 56(%rsp)
 	movq  %rdx, 48(%rsp)
@@ -45,6 +53,14 @@ __xray_FunctionEntry:
 	callq	*%rax
 .Ltmp0:
   // restore the registers
+	movupd	184(%rsp), %xmm0
+	movupd	168(%rsp), %xmm1
+	movupd	152(%rsp), %xmm2
+	movupd	136(%rsp), %xmm3
+	movupd	120(%rsp), %xmm4
+	movupd	104(%rsp), %xmm5
+	movupd	88(%rsp) , %xmm6
+	movupd	72(%rsp) , %xmm7
 	movq	64(%rsp), %rdi
 	movq  56(%rsp), %rax
 	movq  48(%rsp), %rdx
@@ -52,7 +68,7 @@ __xray_FunctionEntry:
 	movq	32(%rsp), %rcx
 	movq	24(%rsp), %r8
 	movq	16(%rsp), %r9
-	addq	$72, %rsp
+	addq	$200, %rsp
 	popq	%rbp
 	retq
 .Ltmp1:
@@ -67,11 +83,12 @@ __xray_FunctionExit:
 	// Save the important registers first. Since we're assuming that this
 	// function is only jumped into, we only preserve the registers for
 	// returning.
-	// FIXME: Figure out whether this is sufficient.
 	pushq	%rbp
 	.cfi_def_cfa_offset 16
-	subq	$24, %rsp
+	subq	$56, %rsp
 	.cfi_def_cfa_offset 32
+	movupd	%xmm0, 40(%rsp)
+	movupd	%xmm1, 24(%rsp)
 	movq	%rax, 16(%rsp)
 	movq	%rdx, 8(%rsp)
 	movq	_ZN6__xray19XRayPatchedFunctionE(%rip), %rax
@@ -83,9 +100,11 @@ __xray_FunctionExit:
 	callq	*%rax
 .Ltmp2:
   // Restore the important registers.
+	movupd	40(%rsp), %xmm0
+	movupd	24(%rsp), %xmm1
 	movq	16(%rsp), %rax
 	movq	8(%rsp), %rdx
-	addq	$24, %rsp
+	addq	$56, %rsp
 	popq	%rbp
 	retq
 .Ltmp3: